It has been suggested that Period (geology) be merged into this article or section. (Discuss)

Diagram of geological time scale.

The geological time scale is used by geologists and other scientists to describe the timing and relationships between events that have occurred during the history of Earth. The table of geologic periods presented here agrees with the dates and nomenclature proposed by the International Commission on Stratigraphy, and uses the standard color codes of the United States Geological Survey. Image File history File links Mergefrom. ... A geologic period is a subdivision of geologic time that divides an era into smaller timeframes. ... The Geologist by Carl Spitzweg A geologist is a contributor to the science of geology, studying the physical structure and processes of the Earth and planets of the solar system (see planetary geology). ... For a List of scientists, see: List of anthropologists List of astronomers List of biologists List of chemists List of computer scientists List of economists List of engineers List of geologists List of inventors List of mathematicians List of meteorologists List of physicists Scientist pairs List of scientist pairs See... Geological time put in a diagram called a geological clock, showing the relative lengths of the eons of the Earths history. ... In geology, a period or age is a time span of many millions of years that are assumed to have had similar characteristics. ... For other uses, see Scientific classification (disambiguation). ... The International Commission on Stratigraphy concerns itself with stratigraphy on a global scale. ... InsertSLUTTY WHORES≤ non-formatted text here{| class=toccolours border=1 cellpadding=4 style=float: right; margin: 0 0 1em 1em; width: 20em; border-collapse: collapse; font-size: 95%; clear: right; |+ United States Geological Survey |- |style= align=center colspan=2| [[Image:USGS logo. ...

Evidence from radiometric dating indicates that the Earth is about 4.570 billion years old. The geological or deep time of Earth's past has been organized into various units according to events which took place in each period. Different spans of time on the time scale are usually delimited by major geological or paleontological events, such as mass extinctions. For example, the boundary between the Cretaceous period and the Paleogene period is defined by the extinction event, known as the Cretaceous–Tertiary extinction event, that marked the demise of the dinosaurs and of many marine species. Older periods which predate the reliable fossil record are defined by absolute age. Radiometric dating (often called radioactive dating) is a technique used to date materials, based on a comparison between the observed abundance of particular naturally occurring radioactive isotopes and their known decay rates. ... Earth as seen from Apollo 17 Modern geologists consider the age of the Earth to be around 4. ... Deep time is the theory that Earth is billions of years old and thus had a long history of development and change. ... This article includes a list of works cited but its sources remain unclear because it lacks in-text citations. ... Paleontology, palaeontology or palæontology (from Greek: paleo, ancient; ontos, being; and logos, knowledge) is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. ... An extinction event (also extinction-level event, ELE) is a period in time when a large number of species die out. ... // The Cretaceous Period (pronounced ) is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic Period (i. ... Paleogene (alternatively Palaeogene) period is a unit of geologic time that began 65 and ended 23 million years ago. ... An extinction event (also known as: mass extinction; extinction-level event, ELE) occurs when there is a sharp decrease in the number of species in a relatively short period of time. ... Artists reconstruction of a major impact event. ... Orders & Suborders Saurischia Sauropodomorpha Theropoda Ornithischia Thyreophora Ornithopoda Marginocephalia Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. ... For other uses, see Species (disambiguation). ...

Graphical timelines

The second and third timelines are each subsections of their preceding timeline as indicated by asterisks.

The Holocene (the latest epoch) is too small to be shown clearly on this timeline. The Holocene epoch is a geological period, which began approximately 11,550 calendar years BP (about 9600 BC) and continues to the present. ... Look up epoch in Wiktionary, the free dictionary. ...

Terminology

The largest defined unit of time is the supereon composed of Eons. Eons are divided into Eras, which are in turn divided into Periods, Epochs and Stages. At the same time paleontologists define a system of faunal stages, of varying lengths, based on changes in the observed fossil assemblages. In many cases, such faunal stages have been adopted in building the geological nomenclature, though in general there are far more recognized faunal stages than defined geological time units. In general usage, an eon (sometimes spelled æon) is an arbitrarily designated period of time. ... A geologic era is a subdivision of geologic time that is a separate classification that divides the Phanerozoic Eon into three parts timeframes. ... A geologic period is a subdivision of geologic time that divides an era into smaller timeframes. ... A division of geologic time less than a period and greater than an age. ... Faunal stages are a subdivision of geologic time used primarily by paleontologists who study fossils rather than by geologists who study rock formations. ...

Geologists tend to talk in terms of Upper/Late, Lower/Early and Middle parts of periods and other units , such as "Upper Jurassic", and "Middle Cambrian". Upper, Middle, and Lower are terms applied to the rocks themselves, as in "Upper Jurassic sandstone," while Late, Middle, and Early are applied to time, as in "Early Jurassic deposition" or "fossils of Early Jurassic age." The adjectives are capitalized when the subdivision is formally recognized, and lower case when not; thus "early Miocene" but "Early Jurassic." Because geologic units occurring at the same time but from different parts of the world can often look different and contain different fossils, there are many examples where the same period was historically given different names in different locales. For example, in North America the Lower Cambrian is referred to as the Waucoban series that is then subdivided into zones based on trilobites. The same timespan is split into Tommotian, Atdabanian and Botomian stages in East Asia and Siberia. A key aspect of the work of the International Commission on Stratigraphy is to reconcile this conflicting terminology and define universal horizons that can be used around the world. The Geologist by Carl Spitzweg A geologist is a contributor to the science of geology, studying the physical structure and processes of the Earth and planets of the solar system (see planetary geology). ... The Jurassic Period is a major unit of the geologic timescale that extends from about 199. ... For other uses, see Cambrian (disambiguation). ... This article is about the geological formation. ... Deposition is a word used in many fields to describe different processes: In law, deposition is the taking of testimony outside of court. ... For other uses, see Fossil (disambiguation). ... North American redirects here. ... For other uses, see Cambrian (disambiguation). ... Orders Agnostida Redlichiida Corynexochida Lichida Nektaspida? Phacopida Proetida Asaphida Harpetida Ptychopariida Trilobites are extinct arthropods in the class Trilobita. ... The Tommotian Age is an early part of the Cambrian period. ... The Atdabanian period of the Early Cambrian epoch lasted from ca 530 to ca 524 Mya. ... This article is about the geographical region. ... This article is about Siberia as a whole. ...

History of the time scale

Main article: history of geology

Main article: history of paleontology

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Earth history mapped to 24 hours

The principles underlying geologic (geological) time scales were laid down by Nicholas Steno in the late 17th century. Steno argued that rock layers (or strata) are laid down in succession, and that each represents a "slice" of time. He also formulated the principle of superposition, which states that any given stratum is probably older than those above it and younger than those below it. While Steno's principles were simple, applying them to real rocks proved complex. Over the course of the 18th century geologists realized that: Wikipedia does not yet have an article with this exact name. ... The history of paleontology has been an ongoing effort to understand the history of life on Earth by understanding the fossil record left behind by living organisms. ... Image File history File links Question_book-3. ... Nicolaus Steno. ... See here for the superposition principle of physics. ...

1. Sequences of strata were often eroded, distorted, tilted, or even inverted after deposition;
2. Strata laid down at the same time in different areas could have entirely different appearances;
3. The strata of any given area represented only part of the Earth's long history.

A comparative geological timescale

The first serious attempts to formulate a geological time scale that could be applied anywhere on Earth took place in the late 18th century. The most influential of those early attempts (championed by Abraham Werner, among others) divided the rocks of the Earth's crust into four types: Primary, Secondary, Tertiary, and Quaternary. Each type of rock, according to the theory, formed during a specific period in Earth history. It was thus possible to speak of a "Tertiary Period" as well as of "Tertiary Rocks." Indeed, "Tertiary" (now Paleocene-Pliocene) and "Quaternary" (now Pleistocene-Holocene) remained in use as names of geological periods well into the 20th century. It has been suggested that this article or section be merged into sediment. ... This article is about Earth as a planet. ... Abraham Gottlob Werner Abraham Gottlob Werner (1749 or 1750 - 1817), was born in Wehrau, a city in Prussian Silesia, southeastern Germany. ... Look up Crust in Wiktionary, the free dictionary. ...

In opposition to the then-popular Neptunist theories expounded by Werner (that all rocks had precipitated out of a single enormous flood), a major shift in thinking came with the reading by James Hutton of his Theory of the Earth; or, an Investigation of the Laws Observable in the Composition, Dissolution, and Restoration of Land Upon the Globe before the Royal Society of Edinburgh in March and April 1785, events which "as things appear from the perspective of the twentieth century, James Hutton in those reading became the founder of modern geology"^[1] What Hutton proposed was that the interior of the Earth was hot, and that this heat was the engine which drove the creation of new rock: land was eroded by air and water and deposited as layers in the sea; heat then consolidated the sediment into stone, and uplifted it into new lands. This theory was dubbed "Plutonist" in contrast to the flood-oriented theory. Neptunism is a discredited theory of geology proposed in the late 18th century and early 19th century that proposed rocks formed from the crystallization of minerals in the early Earths oceans. ... James Hutton, painted by Abner Lowe. ... The Royal Society of Edinburghs Building on the corner of George St. ...

The identification of strata by the fossils they contained, pioneered by William Smith, Georges Cuvier, Jean d'Omalius d'Halloy and Alexandre Brogniart in the early 19th century, enabled geologists to divide Earth history more precisely. It also enabled them to correlate strata across national (or even continental) boundaries. If two strata (however distant in space or different in composition) contained the same fossils, chances were good that they had been laid down at the same time. Detailed studies between 1820 and 1850 of the strata and fossils of Europe produced the sequence of geological periods still used today. William Smith. ... Georges Cuvier Baron Georges Léopold Chrétien Frédéric Dagobert Cuvier (August 23, 1769–May 13, 1832) was a French naturalist and zoologist. ... Jean Baptiste Julien dOmalius dHalloy (1783-1875), Belgian geologist, was born at Liège, Belgium on February 16, 1783. ... Alexandre Brogniart (1770-1840) was a distinguished French geologist, who also became director of the Sèvres, France porcelain manufactory. ... For other uses, see Europe (disambiguation). ...

The process was dominated by British geologists, and the names of the periods reflect that dominance. The "Cambrian," (the Roman name for Wales) and the "Ordovician," and "Silurian", named after ancient Welsh tribes, were periods defined using stratigraphic sequences from Wales.^[2] The "Devonian" was named for the English county of Devon, and the name "Carboniferous" was simply an adaptation of "the Coal Measures," the old British geologists' term for the same set of strata. The "Permian" was named after Perm, Russia, because it was defined using strata in that region by a Scottish geologist Roderick Murchison. However, some periods were defined by geologists from other countries. The "Triassic" was named in 1834 by a German geologist Friedrich Von Alberti from the three distinct layers (Latin trias meaning triad) —red beds, capped by chalk, followed by black shales— that are found throughout Germany and Northwest Europe, called the 'Trias'. The "Jurassic" was named by a French geologist Alexandre Brogniart for the extensive marine limestone exposures of the Jura Mountains. The "Cretaceous" (from Latin creta meaning 'chalk') as a separate period was first defined by a Belgian geologist Jean d'Omalius d'Halloy in 1822, using strata in the Paris basin^[3] and named for the extensive beds of chalk (calcium carbonate deposited by the shells of marine invertebrates). This article is about the country. ... This article is about Welsh people who are considered to be an ethnic group and a nation. ... For other uses, see England (disambiguation). ... The traditional counties as usually portrayed. ... For other uses, see Devon (disambiguation). ... Location Position of Perm in Russia Government Country Federal district Federal subject Russia Volga Federal District Perm Krai Mayor Igor Nikolayevich Shubin Geographical characteristics Area  - City    - Land    - Water 799. ... This article is about the country. ... Sir Roderick Murchison Sir Roderick Impey Murchison (February 19, 1792 – October 22, 1871), was an influential Scottish geologist who first described and investigated the Silurian era. ... Dr. Friedrich August von Alberti (September 4, 1795—September 12, 1878) was a German geologist who recognized the unity of the three characteristic strata that compose the Triassic period (Latin trias meaning triad), in a ground-breaking 1834 publication[1]. From the fossils contained in the three distinct layers— of... For other uses, see Latins and Latin (disambiguation). ... Red beds are strata of sedimentary rock that are red due to the presence of iron oxides. ... For other uses, see Chalk (disambiguation). ... Shale Shale is a fine-grained sedimentary rock whose original constituents were clays or muds. ... North-West Europe is not a well defined term. ... Alexandre Brogniart (1770-1840) was a distinguished French geologist, who also became director of the Sèvres, France porcelain manufactory. ... For other uses, see Limestone (disambiguation). ... Looking towards Lelex from near to Crêt de la Neige The Jura folds are located north of the main Alpine orogenic front and are being continually deformed, accommodating the northwards compression from Alpine folding. ... For other uses, see Chalk (disambiguation). ... Jean Baptiste Julien dOmalius dHalloy (1783-1875), Belgian geologist, was born at Liège, Belgium on February 16, 1783. ... The Paris Basin is one of the major geological regions of France having developed since the Triassic on a basement formed by the Variscan orogeny. ... Calcium carbonate is a chemical compound, with the chemical formula CaCO3. ... Invertebrate is an English word that describes any animal without a spinal column. ...

British geologists were also responsible for the grouping of periods into Eras and the subdivision of the Tertiary and Quaternary periods into epochs.

When William Smith and Sir Charles Lyell first recognized that rock strata represented successive time periods, time scales could be estimated only very imprecisely since various kinds of rates of change used in estimation were highly variable. While creationists had been proposing dates of around six or seven thousand years for the age of the Earth based on the Bible, early geologists were suggesting millions of years for geologic periods with some even suggesting a virtually infinite age for the Earth. Geologists and paleontologists constructed the geologic table based on the relative positions of different strata and fossils, and estimated the time scales based on studying rates of various kinds of weathering, erosion, sedimentation, and lithification. Until the discovery of radioactivity in 1896 and the development of its geological applications through radiometric dating during the first half of the 20th century (pioneered by such geologists as Arthur Holmes) which allowed for more precise absolute dating of rocks, the ages of various rock strata and the age of the Earth were the subject of considerable debate. William Smith. ... Charles Lyell Sir Charles Lyell (November 14, 1797 – February 22, 1875), British geologist, and popularizer of uniformitarianism. ... Interstate road cut through limestone and shale strata in eastern Tennessee In geology and related fields, a stratum (plural: strata) is a layer of rock or soil with internally consistent characteristics that distinguishes it from contiguous layers. ... Creationism is generally the belief that the universe was created by a deity, or alternatively by one or more powerful and intelligent beings. ... Earth as seen from Apollo 17 Modern geologists consider the age of the Earth to be around 4. ... For other uses, see Bible (disambiguation). ... A paleontologist carefully chips rock from a column of dinosaur vertebrae. ... For other uses, see Fossil (disambiguation). ... Weathering is the decomposition of rocks, soils and their minerals through direct contact with the Earths atmosphere. ... For morphological image processing operations, see Erosion (morphology). ... Sedimentation describes the motion of particles in solutions or suspensions in response to an external force such as gravity, centrifugal force or electric force. ... Lithification (from the Greek word lithos meaning rock and the Latin-derived suffix -ific) is the process whereby sediments compact under pressure, expel connate fluids, and gradually become solid rock. ... Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting radiation in the form of particles or electromagnetic waves. ... Radiometric dating (often called radioactive dating) is a technique used to date materials, based on a comparison between the observed abundance of particular naturally occurring radioactive isotopes and their known decay rates. ... Arthur Holmes (January 14, 1890 – September 20, 1965) was a British geologist. ... This article is about Earth as a planet. ...

In 1977, the Global Commission on Stratigraphy (now the International Commission on Stratigraphy) started an effort to define global references (Global Boundary Stratotype Sections and Points) for geologic periods and faunal stages. The commission's most recent work is described in the 2004 geologic time scale of Gradstein et al.^[4]. A UML model for how the timescale is structured, relating it to the GSSP, is also available^[5]. The International Commission on Stratigraphy concerns itself with stratigraphy on a global scale. ... A Global Boundary Stratotype Section and Point, abbreviated GSSP, is an internationally agreed upon stratigraphic section which serves as the reference section for a particular boundary on the geologic timescale. ...

Table of geologic time

The following table summarizes the major events and characteristics of the periods of time making up the geologic time scale. As above, this time scale is based on the International Commission on Stratigraphy. (See lunar geologic timescale for a discussion of the geologic subdivisions of Earth's moon.) The height of each table entry does not correspond to the duration of each subdivision of time. The lunar geologic timescale (or perhaps more properly the selenologic timescale) divides the history of Earths Moon into six generally recognized geologic periods: Copernician Period : 1100 MY to present Eratosthenian Period : 3200 MY to 1100 MY Upper Imbrian Epoch : 3800 MY to 3200 MY Lower Imbrian Epoch : 3850 MY...

In general usage, an eon (sometimes spelled æon) is an arbitrarily designated period of time. ... A geologic era is a subdivision of geologic time that is a separate classification that divides the Phanerozoic Eon into three parts timeframes. ... A geologic period is a subdivision of geologic time that divides an era into smaller timeframes. ... Look up epoch in Wiktionary, the free dictionary. ... Faunal stages are a subdivision of geologic time used primarily by paleontologists who study fossils rather than by geologists who study rock formations. ... A geologic age is a time period on the geologic timescale delimited by major geologic or paleontologic events. ... During the Phanerozoic the biodiversity shows a steady but not monotonic increase from near zero to several thousands of genera. ... Mammals are the dominant creatures of Cenozoic. ... Neogene Period is a unit of geologic time consisting of the Miocene, Pliocene, Pleistocene, and Holocene epochs. ... The Holocene epoch is a geological period, which began approximately 11,550 calendar years BP (about 9600 BC) and continues to the present. ... The Quaternary Period is the geologic time period from the end of the Pliocene Epoch roughly 1. ... Central New York City. ... Glaciation, often called an ice age, is a geological phenomenon in which massive ice sheets form in the Arctic and Antarctic and advance toward the equator. ... Three temperature records, the GRIP one clearly showing the Younger Dryas event at around 11 kyr BP The Younger Dryas stadial, named after the alpine / tundra wildflower Dryas octopetala, and also referred to as the Big Freeze [1], was a brief (approximately 1300 ± 70 years [1]) cold climate period following... The Sahara is the worlds second largest desert (second to Antarctica), over 9,000,000 km² (3,500,000 mi²), located in northern Africa and is 2. ... For other uses, see City (disambiguation). ... // The Paleolithic is a prehistoric era distinguished by the development of stone tools. ... An array of Neolithic artifacts, including bracelets, axe heads, chisels, and polishing tools. ... Stone Age fishing hook. ... This article is about the period. ... The Chalcolithic (Greek khalkos + lithos copper stone) period or Copper Age period (also known as the Eneolithic (Aeneolithic)), is a phase in the development of human culture in which the use of early metal tools appeared alongside the use of stone tools. ... The Bronze Age is a period in a civilizations development when the most advanced metalworking has developed the techniques of smelting copper from natural outcroppings and alloys it to cast bronze. ... Iron Age Axe found on Gotland This article is about the archaeological period known as the Iron Age, for the mythological Iron Age see Iron Age (mythology). ... The table gives a rough picture of the relationships between the various principal cultures of Prehistory outside the Americas, Antarctica, Australia and Oceania. ... Classical antiquity is a broad term for a long period of cultural history centered on the Mediterranean Sea, which begins roughly with the earliest-recorded Greek poetry of Homer (7th century BC), and continues through the rise of Christianity and the fall of the Western Roman Empire (5th century AD... Ancient Rome was a civilization that grew from a small agricultural community founded on the Italian Peninsula circa the 9th century BC to a massive empire straddling the Mediterranean Sea. ... The Middle Ages formed the middle period in a traditional schematic division of European history into three ages: the classical civilization of Antiquity, the Middle Ages, and modern times, beginning with the Renaissance. ... In many works of fiction, events may simply be described as taking place in the Present Day. This can mean one of three things: The events depicted take place at the time the media is viewed or read; The events depicted take place at the exact date in history when... Names for archaeological periods vary enormously from region to region. ... Mount Tambora (or Tomboro) is an active stratovolcano on Sumbawa island, Indonesia. ... This article is about volcanoes in geology. ... April 5-12: Mount Tambora explodes, changing climate. ... Development of global average temperatures during the last thousand years. ... Year 1816 (MDCCCXVI) was a leap year starting on Monday (link will display the full calendar) of the Gregorian calendar (or a leap year starting on Saturday of the 12-day slower Julian calendar). ... For other uses, see Europe (disambiguation). ... North American redirects here. ... A volcanic winter is the reduction in temperature caused by volcanic ash and droplets of sulfuric acid obscuring the sun, usually after a volcanic eruption. ... Air redirects here. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... Parts per million (ppm) is a measure of concentration that is used where low levels of concentration are significant. ... Global warming refers to the increase in the average temperature of the Earths near-surface air and oceans in recent decades and its projected continuation. ... Variations in CO2, temperature and dust from the Vostok ice core over the last 450,000 years For current global climate change, see Global warming. ... National and international science academies and professional societies have assessed the current scientific opinion on climate change, in particular recent global warming. ... Look up anthropogenic in Wiktionary, the free dictionary. ... A Watt steam engine, the steam engine that propelled the Industrial Revolution in Britain and the world. ... The Pleistocene epoch (IPA: ) on the geologic timescale is the period from 1,808,000 to 11,550 years BP. The Pleistocene epoch had been intended to cover the worlds recent period of repeated glaciations. ... Late Pleistocene (also known as Upper Pleistocene or the Tarantian) is a stage of the Pleistocene Epoch. ... The Tyrrhenian Stage is the last faunal stage of the Pleistocene in Europe. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... It has been suggested that New World Pleistocene extinctions be merged into this article or section. ... This article is about modern humans. ... Glaciation, often called an ice age, is a geological phenomenon in which massive ice sheets form in the Arctic and Antarctic and advance toward the equator. ... Air redirects here. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... Temperature proxies for the last 40,000 years The Last Glacial Maximum refers to the time of maximum extent of the ice sheets during the last glaciation, approximately 21 thousand years ago. ... Before Present (BP) years are the units of time (counted backwards to the past) used to report raw radiocarbon ages and dates referenced to the BP scale origin in the year AD 1950 (identical to 1950 CE). ... The Lower Paleolithic (or Lower Palaeolithic) is the earliest subdivision of the Paleolithic or Old Stone Age. ... The Middle Paleolithic (or Middle Palaeolithic) is the second subdivision of the Paleolithic or Old Stone Age as it is understood in Europe, Africa and Asia. ... The Upper Paleolithic (or Upper Palaeolithic) is the third and last subdivision of the Paleolithic or Old Stone Age as it is understood in Europe, Africa and Asia. ... The Venus of Lespugue is a Venus figurine, a statuette of a nude female figure from approximately 25,000 BC. It was discovered in 1922 in the Rideaux cave of Lespugue (Haute-Garonne) in the foothills of the Pyrenees. ... The Mediterranean Sea is an intercontinental sea positioned between Europe to the north, Africa to the south and Asia to the east, covering an approximate area of 2. ... For other uses, see Europe (disambiguation). ... Lake Toba (Indonesian: Danau Toba) is a lake, 100 km long and 30 km wide, and 505 m. ... A supervolcano is a volcano that produces the largest and most voluminous kinds of eruption on Earth. ... A volcanic winter is the reduction in temperature caused by volcanic ash and droplets of sulfuric acid obscuring the sun, usually after a volcanic eruption. ... Eruption column rising, Mount Redoubt, Alaska According to the Toba catastrophe theory, modern human evolution was affected by a recent, large volcanic event. ... The Middle Pleistocene is the central part of the Pleistocene Epoch from about 780,000 YA to the penultimate cold pulse at about 125,000 YA. Millions of Years Categories: Graphical timelines | Geology stubs | Pleistocene ... Early Pleistocene (also known as Lower Pleistocene, or Calabrian) is a stage of the Pleistocene Epoch. ... In the geologic timescale, Gelasian is an ICS stage, part of the Pliocene epoch of the Neogene period. ... The Pliocene epoch (spelled Pleiocene in some older texts) is the period in the geologic timescale that extends from 5. ... In the geologic timescale, Piacenzian is an ICS stage, part of the Pliocene epoch of the Neogene period. ... The Blancan North American Stage on the geologic timescale is the length of time, stage, from 4,750,000 to 1,808,000 years BP.[1][2] It is based upon North American faunal assemblages and is consistent with North American Land Mammal Ages (NALMA). ... This term australopithecine refers to two very closely related hominin genera: Australopithecus Paranthropus When used alone, the term refers to both genera together. ... Classes Caudofoveata Aplacophora Polyplacophora Monoplacophora Bivalvia Scaphopoda Gastropoda Cephalopoda † Rostroconchia The mollusks or molluscs are the large and diverse phylum Mollusca, which includes a variety of familiar creatures well-known for their decorative shells or as seafood. ... Binomial name Leakey et al, 1964 Homo habilis (pronounced ) (handy man, skillful person) is a species of the genus Homo, which lived from approximately 2. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... The Miocene Epoch is a period of time that extends from about 23. ... The Messinian period is the last part of the Miocene epoch. ... Variations in CO2, temperature and dust from the Vostok ice core over the last 400 000 years For the animated movie, see Ice Age (movie). ... // Orogeny (Greek for mountain generating) is the process of mountain building, and may be studied as a tectonic structural event, as a geographical event and a chronological event, in that orogenic events cause distinctive structural phenomena and related tectonic activity, affect certain regions of rocks and crust and happen within... Northern hemisphere highlighted in yellow. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... For other uses, see Bird (disambiguation). ... Species - Donkey - African Wild Ass - Domestic Horse - Wild Horse - Grevys Zebra - Onager - Kiang - Plains Zebra - Cape Mountain Zebra - Hartmanns Mountain Zebra Equidae is the family of horse-like animals, order Perissodactyla. ... This article is about the prehistoric elephant-like animal. ... For other uses, see Grass (disambiguation). ... This article is about the biological superfamily. ... Binomial name Brunet et al, 2002 Sahelanthropus tchadensis is a fossil ape, thought to have lived approximately 7 million years ago. ... The Kaikoura Orogeny is a New Zealand orogeny that has given birth to the Southern Alps. ... The Southern Alps is a mountain range which runs along the western side of the South Island of New Zealand. ... Satellite image of the Carpathians. ... Central Europe is the region lying between the variously and vaguely defined areas of Eastern and Western Europe. ... Eastern Europe is a concept that lacks one precise definition. ... The term Middle Miocene disruption, alternatively the Middle Miocene extinction or Middle Miocene extinction peak, refers to a wave of extinctions of terrestrial and aquatic life forms that occurred around the middle of the Miocene Epoch, c. ... Photosynthesis splits water to liberate O2 and fixes CO2 into sugar The leaf is the primary site of photosynthesis in plants. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... Millions of Years Categories: Graphical timelines | Geology stubs ... In the geologic timescale, the Burdigalian is the age of the Miocene epoch of the Neogene period of the Cenozoic era of the Phanerozoic eon that is between 20. ... Millions of Years Categories: Graphical timelines | Geology stubs ... Millions of Years Categories: Graphical timelines | Geology stubs ... In the geologic timescale, the Aquitanian is the age of the Miocene epoch of the Neogene period of the Cenozoic era of the Fanerozoic eon that is comprehended between 23 million 30 thousand and 20 million 430 thousand years ago, approximatedly. ... Paleogene (alternatively Palaeogene) period is a unit of geologic time that began 65 and ended 23 million years ago. ... The Oligocene epoch is a geologic period of time that extends from about 34 million to 23 million years before the present. ... The Chattian (also known as Chickasawhayan) is the second and final of two stages of the Oligocene Epoch. ... This article is about evolution in biology. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants or angiosperms are the most widespread group of land plants. ... The Rupelian (also known as Stampian, Tongrian, Latdorfian, or Vicksburgian) is the first of two stages of the Oligocene Epoch. ... hfajhfiudshfas == == == --24. ... The Priabonian (also known as Jacksonian or Runangan) is the final stage of the Eocene Epoch. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... Families Oxyaenidae Hyaenodontidae The creodonts were an extinct order of mammals that lived from the Paleocene to the Pliocene. ... Condylarthra is an order of Paleocene mammals. ... The Uintatheriidae is a group of extinct mammals that includes Uintatherium. ... Suborders Mysticeti Odontoceti Archaeoceti (extinct) (see text for families) The order Cetacea (IPA: , L. cetus, whale) includes whales, dolphins and porpoises. ... For other uses, see Grass (disambiguation). ... An ice cap is a dome-shaped ice mass that covers less than 50,000 km² of land area (usually covering a highland area). ... Variations in CO2, temperature and dust from the Vostok ice core over the last 400 000 years For the animated movie, see Ice Age (movie). ... The seabed (also sea floor, seafloor, or ocean floor) is the bottom of the ocean. ... For the programming language, see algae (programming language). ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... Parts per million (ppm) is a measure of concentration that is used where low levels of concentration are significant. ... The Laramide orogeny was a period of mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago, and ended 35 to 55 million years ago. ... The Sevier orogeny was a mountain-building event that affected western North America between aproximately 140 million years ago (Ma), and 50 Ma. ... For individual mountains named Rocky Mountain, see Rocky Mountain (disambiguation). ... North American redirects here. ... // Orogeny (Greek for mountain generating) is the process of mountain building, and may be studied as a tectonic structural event, as a geographical event and a chronological event, in that orogenic events cause distinctive structural phenomena and related tectonic activity, affect certain regions of rocks and crust and happen within... Alp redirects here. ... For other uses, see Europe (disambiguation). ... The Bartonian (also known as the Auversian) is a stage of the middle Eocene Epoch. ... The Lutetian is a stage of the middle Eocene Epoch. ... The Ypresian is the first stage of the Eocene Epoch. ... The Paleocene, early dawn of the recent, is a geologic epoch that lasted from 65. ... The Thanetian (also known as the Landenian or the Heersian) is the last stage of the Paleocene Epoch. ... For other uses, see Plant (disambiguation). ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... For other uses, see Bear (disambiguation). ... Hippo can refer to: hippo- is the stem of the Greek word for horse. ... The Alps arose as a result of the pressure exerted on sediments of the Tethys Ocean basin as its Mesozoic and early Cenozoic strata were pushed against the stable Eurasian landmass by the northward-moving African landmass. ... For other uses, see Europe (disambiguation). ... For other uses, see Asia (disambiguation). ... Map of South Asia (see note) This article deals with the geophysical region in Asia. ... For other uses, see Asia (disambiguation). ... Fig 1: The earth in the Early Permian. ... Selandian is a stage of the middle Paleocene Epoch. ... The Danian (also known as the Montian) is the first stage of the Paleocene Epoch. ... The Mesozoic Era is one of three geologic eras of the Phanerozoic eon. ... // The Cretaceous Period (pronounced ) is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic Period (i. ... Geography of the US in the Late Cretaceous Period Late Cretaceous (100mya - 65mya) refers to the second half of the Cretaceous Period, named after the famous white chalk cliffs of southern England, which date from this time. ... The Maastrichtian is the last stage of the Cretaceous period, and therefore of the Mesozoic era. ... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants or angiosperms are the most widespread group of land plants. ... Orders Subclass Apterygota Archaeognatha (bristletails) Thysanura (silverfish) Subclass Pterygota Infraclass Paleoptera (Probably paraphyletic) Ephemeroptera (mayflies) Odonata (dragonflies and damselflies) Infraclass Neoptera Superorder Exopterygota Grylloblattodea (ice-crawlers) Mantophasmatodea (gladiators) Plecoptera (stoneflies) Embioptera (webspinners) Zoraptera (angel insects) Dermaptera (earwigs) Orthoptera (grasshoppers, etc) Phasmatodea (stick insects) Blattodea (cockroaches) Isoptera (termites) Mantodea (mantids) Psocoptera... Superorders Osteoglossomorpha Elopomorpha Clupeomorpha Ostariophysi Protacanthopterygii Sternopterygii Cyclosquamata Scopelomorpha Lampridiomorpha Polymyxiomorpha Paracanthopterygii Polymyxiomorpha Acanthopterygii Teleostei is one of three infraclasses in class Actinopterygii, the ray-finned fishes. ... For other uses, see Ammonite (disambiguation). ... Extinct Orders Aulacocerida Phragmoteuthida Belemnitida Diplobelida Belemnoteuthina Belemnites (or belemnoids) are an extinct group of marine cephalopod, very similar in many ways to the modern squid and closely related to the modern cuttlefish. ... Rudists are a group of bivalves that peaked in abundance and diversity during the late Mesozoic era, particularly in the Cretaceous period, at the end of which they became extinct. ... Subclasses Anomalosdesmata Cryptodonta Heterodonta Paleoheterodonta Palaeotaxodonta Pteriomorphia and see text Mussels in the intertidal zone in Cornwall, England. ... Slate pencil urchin (cidaroid) Group of black, long-spined Caribbean sea urchins, Diadema antillarum (Philippi) Sea urchin roe. ... The sponge, in the phylum Porifera, is a very primitive and specialized animal. ... Orders & Suborders Saurischia Sauropodomorpha Theropoda Ornithischia Thyreophora Ornithopoda Marginocephalia Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. ... Genera See text. ... Genera Aegyptosaurus Andesaurus Antarctosaurus Argentinosaurus Argyrosaurus Bruhathkayosaurus Jainosaurus Paralititan Saltasaurus Titanosaurus For the Titanosaurus featured in the Godzilla film series, click here. ... Genera Lambeosaurinae     Corythosaurus    Lambeosaurus    Parasaurolophus Hadrosaurinae    Anasazisaurus     Anatotitan     Edmontosaurus     Hadrosaurus    Maiasaura    Prosaurolophus    Saurolophus    Shantungosaurus Hadrosaurids or duck-billed dinosaurs are members of the family Hadrosauridae, and include ornithopods such as Edmontosaurus and Parasaurolophus. ... Genera Centrosaurinae    Achelousaurus    Centrosaurus    Einiosaurus    Styracosaurus    Pachyrhinosaurus Ceratopsinae    Chasmosaurus    Diceratops    Pentaceratops    Protoceratops    Torosaurus    Triceratops Ceratopsids, or members of the Ceratopsidae (or Ceratopidae), are a diverse group of marginocephalian dinosaurs like Triceratops and Styracosaurus. ... black: range of Crocodilia Families Gavialidae Alligatoridae Crocodylidae Crocodilia is an order of large reptiles that appeared about 84 million years ago in the Late Cretaceous Period (Campanian stage). ... Subfamilies Mosasaurinae Plioplatecarpinae Tylosaurinae Mosasaurs (from Latin Mosa, the Meuse river where the fossils were first discovered + Greek sauros, lizard) were serpentine marine reptiles, more closely related to snakes than to monitor lizards (Lee 1997). ... For other uses, see Shark (disambiguation). ... For other uses, see Bird (disambiguation). ... Suborders Rhamphorhynchoidea Pterodactyloidea Pterosaurs (TEH-row-sore, winged lizards) were flying reptiles of the clade Pterosauria. ... Families Kollikodontidae (extinct) Ornithorhynchidae - Platypus Tachyglossidae - Echidnas Steropodontidae (extinct) Monotremes are mammals that are best known for laying eggs, instead of giving birth to live young like marsupials and placental mammals (Eutheria). ... This article is about mammals. ... Orders[1] Bobolestes Eomaia Maelestes Montanalestes Murtoilestes Prokennalestes Placentalia Superorder Xenarthra: Cingulata (Armadillos) Pilosa (Sloths, True Anteaters) Superorder Afrotheria: Afrosoricida (Tenrecs, etc. ... For other uses of Gondwana and Gondwanaland, see Gondwana (disambiguation). ... The Laramide orogeny was a period of mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago, and ended 35 to 55 million years ago. ... The Sevier orogeny was a mountain-building event that affected western North America between aproximately 140 million years ago (Ma), and 50 Ma. ... For individual mountains named Rocky Mountain, see Rocky Mountain (disambiguation). ... Air redirects here. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... The Campanian is a stage on the geologic time scale occuring from 83. ... The Santonian is a stage of the Late Cretaceous Epoch. ... The Coniacian is a stage of the Late Cretaceous Epoch. ... The Turonian is a stage of the Late Cretaceous Epoch. ... The Cenomanian (also known as Woodbinian) is the first stage of the Late Cretaceous Epoch. ... The Early Cretaceous (timestratigraphic name) or the Lower Cretaceous (logstratigraphic name), is the earlier of the two major divisions of the Cretaceous period. ... Albian (Fr. ... In the geologic timescale, the Aptian is the age of the Lower Cretaceous epoch of the Cretaceous period of the Mesozoic era of the Phanerozoic eon that is comprehended between 125 and 112 million years ago, approximately. ... The Barremian faunal stage was a period of geological time between 117 and 113 million years ago. ... The Hauterivian is a stage of the Early Cretaceous Epoch. ... In the geologic timescale, Valanginian is an age of the Lower Cretaceous epoch of the Cretaceous period of the Mesozoic era of the Phanerozoic eon. ... In the geologic timescale, Berriasian is an age of the Lower Cretaceous epoch of the Cretaceous period of the Mesozoic era of the Phanerozoic eon. ... The Jurassic Period is a major unit of the geologic timescale that extends from about 199. ... Upper Jurassic (also known as Malm) was an epoch of the Jurassic geologic period. ... The Tithonian (141-135 MYA) is the most recent faunal stage of the Jurassic era. ... Divisions Pinophyta (or Coniferophyta) - Conifers Ginkgophyta - Ginkgo Cycadophyta - Cycads Gnetophyta - Gnetum, Ephedra, Welwitschia Gymnosperm (Gymnospermae) are a group of spermatophyte seed-bearing plants with ovules on the edge or blade of an open sporophyll, which are usually arranged in cone-like structures. ... Orders & Families Cordaitales † Pinales   Pinaceae - Pine family   Araucariaceae - Araucaria family   Podocarpaceae - Yellow-wood family   Sciadopityaceae - Umbrella-pine family   Cupressaceae - Cypress family   Cephalotaxaceae - Plum-yew family   Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers, division Pinophyta, are one of 13 or 14 division level taxa within the Kingdom Plantae. ... Bennettitales is an order of plants in the anthophyte clade that first appeared in the Triassic period and became extinct toward the end of the Cretaceous. ... Families Cycadaceae cycas family Stangeriaceae stangeria family Zamiaceae zamia family Leaves and male cone of Cycas revoluta Cycads are an ancient group of seed plants characterized by a large crown of compound leaves and a stout trunk. ... This article is about the group of pteridophyte plants. ... Orders & Suborders Saurischia Sauropodomorpha Theropoda Ornithischia Thyreophora Ornithopoda Marginocephalia Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. ... Families Brachiosauridae Camarasauridae Cetiosauridae Diplodocidae Euhelopodidae Nemegtosauridae Titanosauridae Vulcanodontidae Sauropoda, the sauropods, are a suborder or infraorder of the saurischian (lizard-hipped) dinosaurs. ... Families Allosauridae    Allosaurinae    ?Carcharodontosaurinae Sinraptoridae Carnosauria is a sub-group of Theropods, a group of predatory dinosaurs. ... Species (type) Stegosaurus was a large herbivorous dinosaur genus from the Upper Jurassic of North America. ... For other uses, see Bird (disambiguation). ... Suborders Lacertilia- Lizards Serpentes - Snakes Amphisbaenia - Worm lizards This article is about the Squamata order of reptiles. ... Families Ichthyosauridae Leptonectidae Mixosauridae Ophthalmosauridae Shastasauridae Stenopterygiidae Teretocnemidae Ichthyosaurs (Greek for fish lizard - ιχθυς meaning fish and σαυρος meaning lizard) were giant marine reptiles that resembled fish and dolphins. ... Families Cimoliasauridae Cryptoclididae Elasmosauridae Plesiosauridae Polycotylidae Plesiosaurs (pronounced ) (Greek: plesios meaning near or close to and sauros meaning lizard) were carnivorous aquatic (mostly marine) reptiles. ... Subclasses Anomalosdesmata Cryptodonta Heterodonta Paleoheterodonta Palaeotaxodonta Pteriomorphia and see text Mussels in the intertidal zone in Cornwall, England. ... For other uses, see Ammonite (disambiguation). ... Extinct Orders Aulacocerida Phragmoteuthida Belemnitida Diplobelida Belemnoteuthina Belemnites (or belemnoids) are an extinct group of marine cephalopod, very similar in many ways to the modern squid and closely related to the modern cuttlefish. ... Subclasses Subclass Perischoechinoidea Order Cidaroida (pencil urchins) Subclass Euechinoidea Superorder Atelostomata Order Cassiduloida Order Spatangoida (heart urchins) Superorder Diadematacea Order Diadematoida Order Echinothurioida Order Pedinoida Superorder Echinacea Order Arbacioida Order Echinoida Order Phymosomatoida Order Salenioida Order Temnopleuroida Superorder Gnathostomata Order Clypeasteroida (sand dollars) Order Holectypoida Wikispecies has information related to... Subclasses Articulata (540 species) Cladida (extinct) Flexibilia (extinct) Camerata (extinct) Disparida (extinct) Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). ... The sponge, in the phylum Porifera, is a very primitive and specialized animal. ... Terebratulids are one of the only two living orders of articulate brachiopods, the other being the Rhynchonellida. ... Superfamilies Pugnacoidea Dimerelloidea Norelloidea Hemithiridoidea Ancistrorhynchoidea† Rhynchotrematoidea† Uncinuloidea† Camarotoechioidea† Rhynchotetradoidea† Lambdarinoidea† Wellerelloidea† Rhynchoporoidea† Stenoscismatoidea† See text for genera. ... Diversity About 4000 genera Subphyla and classes See Classification Brachiopods (from Latin bracchium, arm + New Latin -poda, foot) are a nearly extinct, small phylum of benthic invertebrates. ... For other uses, see Pangaea (disambiguation). ... For other uses of Gondwana and Gondwanaland, see Gondwana (disambiguation). ... Laurasia was a supercontinent that most recently existed as a part of the split of the Pangaean supercontinent in the late Mesozoic era. ... The Nevadan Orogeny was a major mountain building event that took place along the western edge of ancient North America between the Mid to Late Jurassic(between about 180 and 146 million years ago). ... The Rangitata Orogeny (an orogeny named after the Rangitata River), was a long period of uplift and collision in New Zealand. ... The Cimmerian plate is an ancient tectonic plate that comprises parts of present-day Turkey, Iran, Afghanistan, and Tibet. ... The Kimmeridgian is a stage of the Late Jurassic Epoch. ... The Oxfordian is the first stage of the Late Jurassic Epoch. ... The Middle Jurassic, called the Dogger in the European system of classification, is the second epoch of the Jurassic period. ... The Callovian is a stage on the geologic time scale occuring from 164. ... In the geologic timescale, the Bathonian is the age of the Middle Jurassic epoch of the Jurassic period of the Mesozoic era of the Phanerozoic eon that is comprehended between 167 million 700 thousand and 164 million 700 thousand years ago, approximatedly. ... In the geologic timescale, the Bajocian is the age of the Middle Jurassic epoch of the Jurassic period of the Mesozoic era of the Fanerozoic eon that is comprehended between 171 million 600 thousand and 167 million 700 thousand years ago, approximatedly. ... The Aalenian is a subdivision of the Middle Jurassic period of the geologic timescale that extends from about 175. ... Massive cliffs in Zion Canyon consist of Lower Jurassic formations, including (from bottom to top): the Wingate Sandstone, the Kayenta Formation, and the massive Navajo Sandstone. ... The Toarcian Stage was the last faunal stage of the Early Jurassic period. ... The Pliensbachian (also known as Charmouthian) is a stage of the Early Jurassic Epoch. ... The Sinemurian is a stage of the Early Jurassic Epoch. ... The Hettangian is the first stage of the Early Jurassic Epoch. ... The Triassic is a geologic period that extends from about 251 to 199 Ma (million years ago). ... The Late Triassic (also known as Upper Triassic, or Keuper) is the third and final of three epochs of the Triassic period. ... The Rhaetian Stage is the most recent stage of the Late Triassic. ... Clades Crurotarsi Aetosauria Crocodilia (crocodiles) Phytosauria Rauisuchia Ornithodira Aves (birds) Dinosauria Pterosauria Archosaurs (Greek for ruling lizards) are a group of diapsid reptiles that is represented today by birds and crocodiles and which also included the dinosaurs. ... Orders & Suborders Saurischia Sauropodomorpha Theropoda Ornithischia Thyreophora Ornithopoda Marginocephalia Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. ... Families Ichthyosauridae Leptonectidae Mixosauridae Ophthalmosauridae Shastasauridae Stenopterygiidae Teretocnemidae Ichthyosaurs (Greek for fish lizard - ιχθυς meaning fish and σαυρος meaning lizard) were giant marine reptiles that resembled fish and dolphins. ... Families Simosauridae Germanosauridae Nothosauridae Nothosaurs were Triassic marine sauropterygian reptiles that may have lived like seals of today, catching food in water but coming ashore on rocks and beaches. ... Suborders Pterodactyloidea Rhamphorhynchoidea * Pterosaurs (, from the Greek πτερόσαυρος, pterosauros, meaning winged lizard, often referred to as pterodactyls, from the Greek πτεροδάκτυλος, pterodaktulos, meaning winged finger ) were flying reptiles of the clade Pterosauria. ... Clades Procynosuchidae Epicynodontia Galesauridae Eucynodontia Cynognathia Cynognathidae Tritylodontidae Probainognathia Trithelodontidae Mammaliformes Cynodonta, or dog teeth, were one of the most diverse groups of therapsids. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... black: range of Crocodilia Families Gavialidae Alligatoridae Crocodylidae Crocodilia is an order of large reptiles that appeared about 84 million years ago in the Late Cretaceous Period (Campanian stage). ... Groups Edopoidea Edopidae Cochleosauridae Euskelia Eryopoidea Eryopidae Zatrachydidae Dissorophoidea Limnarchia Dvinosauria Archegosauridae Stereospondyli Trematosauroidea Capitosauroidea Metoposauroidea Plagiosauroidea Rhytidosteidae Brachyopoidea Brachyopidae Chigutosauridae Temnospondyli are an important and extremely diverse taxon of small to giant labyrinthodont amphibians that flourished worldwide during the Carboniferous, Permian, and Triassic periods. ... For other uses, see Ammonite (disambiguation). ... Families Suborder Astrocoeiina   Acroporidae   Astrocoeniidae   Pocilloporiidae Suborder Caryophylliina   Caryophylliidae Suborder Dendrophylliina   Dendrophylliidae Suborder Faviina   Astrangiidae   Faviidae   Meandrinidae   Mirulinidae   Mussidae   Oculinidae   Pectiniidae   Trachyphyllidae Suborder Fungiina   Agariciidae   Fungiidae   Poritidae   Siderastreidae   Thamnasteriidae Scleractinia, also called Stony corals, are exclusively marine animals; they are very similar to sea anemones but generate a hard skeleton. ... Superorders Osteoglossomorpha Elopomorpha Clupeomorpha Ostariophysi Protacanthopterygii Sternopterygii Cyclosquamata Scopelomorpha Lampridiomorpha Polymyxiomorpha Paracanthopterygii Polymyxiomorpha Acanthopterygii Teleostei is one of three infraclasses in class Actinopterygii, the ray-finned fishes. ... Orders Subclass Apterygota Archaeognatha (bristletails) Thysanura (silverfish) Subclass Pterygota Infraclass Paleoptera (Probably paraphyletic) Ephemeroptera (mayflies) Odonata (dragonflies and damselflies) Infraclass Neoptera Superorder Exopterygota Grylloblattodea (ice-crawlers) Mantophasmatodea (gladiators) Plecoptera (stoneflies) Embioptera (webspinners) Zoraptera (angel insects) Dermaptera (earwigs) Orthoptera (grasshoppers, etc) Phasmatodea (stick insects) Blattodea (cockroaches) Isoptera (termites) Mantodea (mantids) Psocoptera... South America South America is a continent crossed by the equator, with most of its area in the Southern Hemisphere. ... The Cimmerian plate is an ancient tectonic plate that comprises parts of present-day Turkey, Iran, Afghanistan, and Tibet. ... For other uses, see Asia (disambiguation). ... The Rangitata Orogeny (an orogeny named after the Rangitata River), was a long period of uplift and collision in New Zealand. ... The term northern Australia is generally considered to include the Australian states and territories of Queensland and the Northern Territory. ... Slogan or Nickname: Sunshine State, Smart State Motto(s): Audax at Fidelis (Bold but Faithful) Other Australian states and territories Capital Brisbane Government Constitutional monarchy Governor Quentin Bryce Premier Anna Bligh (ALP) Federal representation  - House seats 28  - Senate seats 12 Gross State Product (2004-05)  - Product ($m)  $158,506 (3rd... NSW redirects here. ... The Norian Stage was a portion of the Triassic geological period. ... The Carnian is a stage on the geologic time scale occuring from 228 +/- 2 to 216. ... The Middle Triassic (also known as Muschelkalk) is the second of three epochs of the Triassic period. ... The Ladinian (also known as the Falangian) is a stage of the Middle Triassic epoch. ... In the geologic timescale, the Anisian is the age of the Middle Triassic epoch of the Triassic period of the Mesozoic era of the Fanerozoic eon that is comprehended between 245 million and 237 million years ago, approximatedly. ... The Early Triassic (also known as Lower Triassic, Buntsandstein, or Scythian) is the first of three epochs of the Triassic period. ... The Olenekian (also known as the Yongningzhenian) is a stage of the Early Triassic epoch. ... The Induan (also known as the Feixianguanian) is the first stage of the Early Triassic epoch. ... The Paleozoic Era (from the Greek palaio, old and zoion, animals, meaning ancient life) is the earliest of three geologic eras of the Phanerozoic eon. ... The Permian is a geologic period that extends from about 299. ... Lopingian is the third of the three epoches of the Permian. ... The Changhsingian (also known as Dorashamian, Dewey Lake, Changxingian, or Changshingian) is the second and final of two stages of the Lopingian epoch and the whole Permian period. ... A landmass is a large continuous area of land. ... In geology, a supercontinent is a land mass comprising more than one continental core, or craton. ... For other uses, see Pangaea (disambiguation). ... The Appalachian Mountains are a system of North American mountains running from Newfoundland and Labrador, Canada to Alabama in the United States, although the northernmost mainland portion ends at the Gaspe Peninsula of Quebec. ... Groups Caseasauria Eupelycosauria    Sphenacodontia       Therapsida          (...mammals) Synapsids (fused arch), formerly known as mammal-like reptiles, are a group of amniotes (reptiles and all their ancestors) that developed one hole in their skull (temporal fenestra) behind each eye, about 320 million years ago (Ma) during the late Carboniferous. ... Orders  Crocodilia - Crocodilians scary crocodiles. ... Groups see text The pelycosaurs (from Greek pelyx meaning bowl and sauros meaning lizard) were primitive Late Paleozoic synapsid amniotes. ... Groups Biarmosuchia Dinocephalia Anomodontia Theriodontia    Cynodontia       (...mammals) Therapsids, previously known as the mammal-like reptiles, are a group of synapsids. ... Orders Testudines(Turtles, tortoises& terrapins) Millerettidae- extinct Nyctiphruretidae- extinct Pareiasauridae- extinct Procolophonidae- extinct The anapsids are a group of amniotes, characterized by skulls without openings near the temples. ... Groups Edopoidea Edopidae Cochleosauridae Euskelia Eryopoidea Eryopidae Zatrachydidae Dissorophoidea Limnarchia Dvinosauria Archegosauridae Stereospondyli Trematosauroidea Capitosauroidea Metoposauroidea Plagiosauroidea Rhytidosteidae Brachyopoidea Brachyopidae Chigutosauridae Temnospondyli are an important and extremely diverse taxon of small to giant labyrinthodont amphibians that flourished worldwide during the Carboniferous, Permian, and Triassic periods. ... For other uses, see Amphibian (disambiguation). ... Coal Example chemical structure of coal Coal is a fossil fuel formed in ecosystems where plant remains were saved by water and mud from oxidization and biodegradation. ... Mature female European Black Pine cone Male cones of a pine A cone (in formal botanical usage: strobilus, plural strobili) is an organ on plants in the division Pinophyta (conifers) that contains the reproductive structures. ... Divisions Pinophyta (or Coniferophyta) - Conifers Ginkgophyta - Ginkgo Cycadophyta - Cycads Gnetophyta - Gnetum, Ephedra, Welwitschia Gymnosperm (Gymnospermae) are a group of spermatophyte seed-bearing plants with ovules on the edge or blade of an open sporophyll, which are usually arranged in cone-like structures. ... The spermatophytes (also known as phanerogams) comprise those plants that produce seeds. ... For other uses, see Moss (disambiguation). ... For other uses, see Beetle (disambiguation). ... For other uses, see Fly (disambiguation) and Flies (disambiguation). ... families See text Spiriferida is an order of extinct articulate brachiopod, fossils of which are known for their long hinge-line, which is often the widest part of the shell. ... Orders Allogromiida Carterinida Fusulinida - extinct Globigerinida Involutinida - extinct Lagenida Miliolida Robertinida Rotaliida Silicoloculinida Spirillinida Textulariida incertae sedis    Xenophyophorea    Reticulomyxa The Foraminifera, or forams for short, are a large group of amoeboid protists with reticulating pseudopods, fine strands that branch and merge to form a dynamic net. ... Families Orthoceratidae Pseudorthoceratidae and many others Orthocerida are an order of extinct nautiloid cephalopods that lived from the Early Ordovician to the Late Triassic (about 500 to 200 million years ago), but were most common and diverse from the Ordovician to the Devonian. ... The Permian-Triassic (P-T or PT) extinction event, sometimes informally called the Great Dying, was an extinction event that occurred approximately 251 million years ago (mya), forming the boundary between the Permian and Triassic geologic periods. ... For the robot vacuum cleaner, see Electrolux Trilobite. ... Graptolites (Graptolithina) are fossil colonial animals known chiefly from the Upper Cambrian through the Mississippian (Lower Carboniferous). ... Blastoids (Blastoidea) are an extinct type of stemmed echinoderm. ... The Ouachita orogeny was a mountain building event that resulted in the folding and faulting of exposed strata in the Ouachita Geosyncline in the southern portion of Laurentia, in what is now Southern United States (~from Texas to Arkansas). ... For other uses, see Europe (disambiguation). ... For other uses, see Asia (disambiguation). ... For other uses, see Asia (disambiguation). ... The Australian continental shelf (light blue) is contiguous with New Guinea, but not with other Pacific islands like New Zealand. ... The MacDonnell Ranges of the Northern Territory, are a 644 km (400 mile) long mountain range located in the center of Australia (23°42′S 132°30′E), and consist of parallel ridges running to the east and west of Alice Springs. ... The Wuchiapingian (also known as Wujiapingian, Djulfian, Longtanian, Rustlerian, Saladoan, Castile, or Dzhulfian) is the first of two stages of the Lopingian epoch of Permian period. ... Guadalupian - the second of the three epoches of the Permian, it lasted from about 270 to 260 million years ago. ... The Capitanian is a stage on the geologic time scale occuring from 265. ... The Wordian (also known as Ufimian) is a stage of the Guadalupian epoch of Permian period. ... The Roadian (also known as Ufimian) is the first stage of the Guadalupian epoch of Permian period. ... Cisuralian is the first of the three epochs of the Permian. ... The Kungurian (also known as Irenian or Filippovian) is the last stage of the Cisuralian epoch of Permian period. ... In the geologic timescale, the Artinskian is the age of the Cisuralian epoch of the Permian period of the Paleozoic era of the Fanerozoic eon that is comprehended between 284 million 400 thousand and 275 million 600 thousand years ago, approximatedly. ... The Sakmarian (also known as Sterlitamakian or Tastubian) is a stage of the Cisuralian epoch of Permian period. ... In the geologic timescale, the Asselian is the age of the Cisuralian epoch of the Permian period of the Paleozoic era of the Fanerozoic eon that is comprehended between 299 million and 294 million 600 thousand years ago, approximatedly. ... The Carboniferous is a geologic period and system that extends from the end of the Devonian period, about 359. ... The Pennsylvanian is an epoch of the Carboniferous period lasting from roughly 325 Ma to 299 Ma (million years ago). ... The Late Pennsylvanian (also known as the Upper Pennsylvanian) is the third and final of three subepochs of the Pennsylvanian epoch of the Carboniferous period. ... The Gzhelian Age is the last of four ages in the Pennsylvanian Epoch of the Carboniferous period. ... Orders     Palaeodictyoptera - extinct     Ephemeroptera (mayflies)     Odonata (dragonflies and damselflies)   Infraclass Neoptera     Blattodea (cockroaches)     Mantodea (mantids)     Isoptera (termites)     Zoraptera     Grylloblattodea (rock crawlers)     Dermaptera (earwigs)     Plecoptera (stoneflies)     Orthoptera (grasshoppers, crickets, katydids)     Phasmatodea (walking sticks, timemas)     Embioptera (webspinners)     Mantophasmatodea (gladiators)    Superorder Hemipterodea     Psocoptera (booklice, barklice)     Phthiraptera (lice)     Hemiptera (true bugs)     Thysanoptera (thrips)    Superorder... The Protodonata or Meganisoptera are an extinct order of very large to gigantic Palaeozoic ((Late Carboniferous to Late Permian) insects, similar in appearance to, and related to, dragonflies. ... The Palaeodictyoptera are an extinct order of medium-sized to very large, primitive Palaeozoic paleopteous insects, characterised by beak-like mouthparts, similarity between fore- and hind wings, and an additional pair of winglets (large Paranotal lobes) in front of the first pair of wings. ... For other uses, see Amphibian (disambiguation). ... Reptilia redirects here. ... Coal Example chemical structure of coal Coal is a fossil fuel formed in ecosystems where plant remains were saved by water and mud from oxidization and biodegradation. ... Species See text. ... Sigillaria is the name of a genus of primitive trees which flourished in the early carboniferous period. ... Species See text Calamites is a genus of extinct arborescent (tree-like) horsetails to which the modern horsetails (genus Equisetum) are closely related. ... Cordaites is an important genus of extinct gymnosperms. ... Air redirects here. ... This article is about the chemical element and its most stable form, or dioxygen. ... Families all extinct Goniatites are an extinct group of ammonoid, which are shelled cephalopods related to squids, belemnites, octopi, and cuttlefish, and more distantly to the nautiloids. ... Orders Allogromiida Carterinida Fusulinida- extinct Globigerinida Involutinida- extinct Lagenida Miliolida Robertinida Rotaliida Silicoloculinida Spirillinida Textulariida incertae sedis    Xenophyophorea    Reticulomyxa The Foraminifera, or forams for short, are a large group of amoeboid protists with reticulating pseudopods, fine strands that branch and merge to form a dynamic net. ... For other uses, see Europe (disambiguation). ... For other uses, see Asia (disambiguation). ... The Kasimovian Age is the third of four ages in the Pennsylvanian Epoch of the Carboniferous period. ... The Middle Pennsylvanian is the second of three subepochs of the Pennsylvanian epoch of the Carboniferous period. ... Moscovian is an epoch of the Pennsylvanian Time Period. ... The Early Pennsylvanian (also known as the Lower Pennsylvanian) is the first of three subepochs of the Pennsylvanian epoch of the Carboniferous period. ... This article needs to be cleaned up to conform to a higher standard of quality. ... The Carboniferous is a geologic period and system that extends from the end of the Devonian period, about 359. ... “Mississippian” redirects here. ... The Late Mississippian (also known as the Upper Mississippian) is the third and final of three subepochs of the Mississippian epoch of the Carboniferous period. ... The Serpukhovian Age is the last of three ages in the Mississippian Epoch of the Carboniferous Period. ... Classes Lycopodiopsida - clubmosses Selaginellopsida - spikemosses Isoetopsida - quillworts The Division Lycopodiophyta (sometimes called Lycophyta) is a tracheophyte subdivision of the Kingdom Plantae. ... Classes Synapsida Sauropsida Amphibia A tetrapod (Greek tetrapoda, four-legged) is a vertebrate animal having four feet, legs or leglike appendages. ... Orders †Stylonuroidea Diener, 1924 †Eurypteroidea Burmeister, 1843 The eurypterids (sea scorpion) were the largest known arthropods that ever lived (with the possible exception of the Arthropleurids). ... Coal Example chemical structure of coal Coal is a fossil fuel formed in ecosystems where plant remains were saved by water and mud from oxidization and biodegradation. ... Brackish redirects here. ... genera Barameda Rhizodus Strepsodus Sauripterus Gooloogongia Notorhizodon Screbinodus Rhizodonts (Order Rhizodontida) are an extinct group of predatory lobe-finned fishes. ... Subclasses and Orders See text. ... Subphyla & Classes Homalozoa Gill & Caster, 1960 Homostelea Homoiostelea Stylophora † Ctenocystoidea Robison & Sprinkle, 1969 Crinozoa Crinoidea Paracrinoidea † Regnéll, 1945 Cystoidea †von Buch, 1846 Asterozoa Ophiuroidea Asteroidea Echinozoa Echinoidea Holothuroidea Ophiocistioidea Helicoplacoidea † Arkarua † Homalozoa † Pelmatozoa † Edrioasteroidea † Blastozoa † Blastoidea † Eocrinoidea †Jaekel, 1899 † = extinct Echinoderms (Phylum Echinodermata, from the Greek for spiny skin... Subclasses Articulata (540 species) Cladida (extinct) Flexibilia (extinct) Camerata (extinct) Disparida (extinct) Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). ... Blastoids (Blastoidea) are an extinct type of stemmed echinoderm. ... Extant Subclasses and Orders Alcyonaria    Alcyonacea    Helioporacea Zoantharia    Antipatharia    Corallimorpharia    Scleractinia    Zoanthidea [1][2]  See Anthozoa for details For other uses, see Coral (disambiguation). ... Classes Stenolaemata Gymnolaemata Phylactolaemata Bryozoans are tiny colonial animals that generally build stony skeletons of calcium carbonate, superficially similar to coral. ... Families all extinct Goniatites are an extinct group of ammonite, which are related to the nautiloids. ... families See text Spiriferida is an order of extinct articulate brachiopod, fossils of which are known for their long hinge-line, which is often the widest part of the shell. ... Orders Agnostida Redlichiida Corynexochida Lichida Nektaspida? Phacopida Proetida Asaphida Harpetida Ptychopariida Trilobites are extinct arthropods in the class Trilobita. ... Orders Palcephalopoda †Plectronocerida †Ellesmerocerida †Actinocerida †Pseudorthocerida †Endocerida †Tarphycerida †Oncocerida †Discosorida Nautilida Neocephalopoda (in part) †Orthocerida †Ascocerida †Bactritida Nautiloids are a group of marine mollusks in the subclass Nautiloidea, which all possess an external shell, the best-known example being the modern nautiluses. ... A glaciation (a created composite term meaning Glacial Period, referring to the Period or Era of, as well as the process of High Glacial Activity), often called an ice age, is a geological phenomenon in which massive ice sheets form in the Arctic and Antarctic and advance toward the equator. ... For other uses of Gondwana and Gondwanaland, see Gondwana (disambiguation). ... The Middle Mississippian is the second of three subepochs of the Mississippian epoch of the Carboniferous period. ... The Viséan Age is the middle of three ages in the Mississippian Epoch of the Carboniferous Period. ... The Early Mississippian (also known as the Lower Mississippian) is the first of three subepochs of the Mississippian epoch of the Carboniferous period. ... The Tournasian Age is one of the three ages in the Mississippian Epoch of the Carboniferous Period. ... For the Celtic language, see Southwestern Brythonic language; for the residents of the English county, see Devon. ... In the geological timescale, the Late Devonian epoch (from 385. ... The Famennian Age is one of two ages in the Late Devonian Period. ... Families Lycopodiaceae Huperziaceae The Class Lycopodiopsida includes the clubmosses. ... Classes Equisetopsida The division Equisetophyta is a taxon in the kingdom Plantae containing primitive land plants. ... This article is about the group of pteridophyte plants. ... A ripe red jalapeño cut open to show the seeds For other uses, see Seed (disambiguation). ... Archaeopteris is an extinct genus of tree-like ferns that many scientists believe to be the first tree. ... The coniferous Coast Redwood, the tallest tree species on earth. ... Archaeopteris is an extinct genus of tree-like ferns that many scientists believe to be the first tree. ... Orders Subclass Apterygota Symphypleona - globular springtails Subclass Archaeognatha (jumping bristletails) Subclass Dicondylia Monura - extinct Thysanura (common bristletails) Subclass Pterygota Diaphanopteroidea - extinct Palaeodictyoptera - extinct Megasecoptera - extinct Archodonata - extinct Ephemeroptera (mayflies) Odonata (dragonflies and damselflies) Infraclass Neoptera Blattodea (cockroaches) Mantodea (mantids) Isoptera (termites) Zoraptera Grylloblattodea Dermaptera (earwigs) Plecoptera (stoneflies) Orthoptera (grasshoppers, crickets... Diversity About 4000 genera Subphyla and classes See Classification Brachiopods (from Latin bracchium, arm + New Latin -poda, foot) are a nearly extinct, small phylum of benthic invertebrates. ... Suborders Columnariina† Cystiphyllina† Streptelasmatina† The Rugosa, also called the Tetracoralla, are an extinct order of coral that were abundant in Middle Ordovician to Late Permian seas. ... The tabulate corals, forming the order Tabulata, are an extinct form of coral. ... Subclasses Articulata (540 species) Cladida (extinct) Flexibilia (extinct) Camerata (extinct) Disparida (extinct) Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). ... Families all extinct Goniatites are an extinct group of ammonoid, which are shelled cephalopods related to squids, belemnites, octopi, and cuttlefish, and more distantly to the nautiloids. ... For other uses, see Ammonite (disambiguation). ... Orders Aulacocerida (extinct) Hematitida  (extinct) Phragmoteuthida  (extinct) Belemnitida  (extinct) Sepiida Sepiolida Spirulida Teuthida Octopoda Vampyromorphida Subclass Coleoidea is the grouping of cephalopods containing all the primarily soft-bodied creatures. ... Orders Antiarchi † Arthrodira † Brindabellaspida † Petalichthyida † Phyllolepida † Ptyctodontida † Rhenanida † Acanthothoraci † ?Pseudopetalichthyida † ?Stensioellida † The Placodermi are armoured prehistoric fishes known from fossils dating from the late Silurian to the end of the Devonian Period. ... Subclasses Coelacanthimorpha - Coelacanths Dipnoi - Lungfishes Tetrapoda Sarcopterygii is traditionally the class of lobe-finned fishes, consisting of lungfish and coelacanths. ... Classes Actinopterygii Sarcopterygii Osteichthyes (IPA: ), also called bony fish, are a taxonomic superclass of fish that includes the ray-finned fish (Actinopterygii) and lobe finned fish (Sarcopterygii). ... Subclasses and Orders See text. ... Groups See text. ... Euramerica (also known as Laurussia) was a minor supercontinent created in the Devonian by the collision of Laurentia and Baltica (Scandian Orogeny). ... The Acadian orogeny is a middle Paleozoic deformation, especially in the northern Appalachians, between Alabama and Newfoundland. ...  Northern Africa (UN subregion)  geographic, including above North Africa or Northern Africa is the northernmost region of the African continent, separated by the Sahara from Sub-Saharan Africa. ... The Appalachian Mountains are a vast system of mountains in eastern North America. ... North American redirects here. ... The Antler orogeny is an orogeny that extensively deformed Paleozoic rocks of the Great Basin in Nevada during Late Devonian and Early Mississipian time. ... The Variscan or Hercynian orogeny is a geologic mountain-building event recorded in the European mountains and hills called the Variscan Belt. ... The Frasnian Age is one of two ages in the Late Devonian Period. ... In the geological timescale, the Middle Devonian epoch (from 397. ... The Givetian (also known as Erian, Senecan, Tioughniogan, Tioughnioga, Taghanic, Taghanican, Genesee, Geneseean) stage is the later stage of the Middle Devonian epoch. ... The Eifelian is one of two faunal stages in the Middle Devonian Period. ... In the geological timescale, the Early Devonian epoch (from 416. ... The Emsian is one of three faunal stages in the Early Devonian Period. ... The Pragian is one of three faunal stages in the Early Devonian epoch. ... The Lochkovian is one of three faunal stages in the Early Devonian epoch. ... For other uses, see Silurian (disambiguation). ... In the geological timescale, the Pridoli epoch (from 418. ... Divisions Non-seed-bearing plants †Rhyniophyta †Zosterophyllophyta Lycopodiophyta †Trimerophytophyta Pteridophyta Superdivision Spermatophyta †Pteridospermatophyta Pinophyta Cycadophyta Ginkgophyta Gnetophyta Magnoliophyta Vascular plants (also known as tracheophytes or higher plants) are those plants that have lignified tissues for conducting water, minerals, and photosynthetic products through the plant. ... For other uses, see Millipede (disambiguation). ... The largest terrestrial arthropods to ever walk the Earth, Arthropleurida resembled long cockroaches living in swamps. ... Classes Placodermi Chondrichthyes Acanthodii Actinopterygii Sarcopterygii Gnathostomata is the group of vertebrates with jaws. ... This article or section does not cite its references or sources. ... Idealized agnatha. ... Orders †Stylonuroidea Diener, 1924 †Eurypteroidea Burmeister, 1843 The eurypterids (sea scorpion) were the largest known arthropods that ever lived (with the possible exception of the Arthropleurids). ... Tabulate Corals lived entirely during the Paleozoic. ... Suborders Columnariina† Cystiphyllina† Streptelasmatina† The Rugosa, also called the Tetracoralla, are an extinct order of coral that were abundant in Middle Ordovician to Late Permian seas. ... Diversity About 4000 genera Subphyla and classes See Classification Brachiopods (from Latin bracchium, arm + New Latin -poda, foot) are a nearly extinct, small phylum of benthic invertebrates. ... Superfamilies Pugnacoidea Dimerelloidea Norelloidea Hemithiridoidea Ancistrorhynchoidea† Rhynchotrematoidea† Uncinuloidea† Camarotoechioidea† Rhynchotetradoidea† Lambdarinoidea† Wellerelloidea† Rhynchoporoidea† Stenoscismatoidea† See text for genera. ... Subclasses Articulata (540 species) Cladida (extinct) Flexibilia (extinct) Camerata (extinct) Disparida (extinct) Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). ... For the robot vacuum cleaner, see Electrolux Trilobite. ... Classes Caudofoveata Aplacophora Polyplacophora Monoplacophora Bivalvia Scaphopoda Gastropoda Cephalopoda † Rostroconchia The mollusks or molluscs are the large and diverse phylum Mollusca, which includes a variety of familiar creatures well-known for their decorative shells or as seafood. ... Graptolites (Graptolithina) are fossil colonial animals known chiefly from the Upper Cambrian through the Mississippian (Lower Carboniferous). ... The Caledonian orogeny is a hypothetical series of events in geologic history explaining a group of highland formations that are very similar in composition, stratigraphy and fossils: the mountains and hills of northern England, Wales, Scotland, Ireland and west Norway. ... For other uses, see England (disambiguation). ... This article is about the country. ... This article is about the country. ... The Scandinavian Mountains, in Swedish Skanderna, Fjällen (the Fells) or Kölen, and in Norwegian Kjølen, with the two latter meaning the Keel, are a mountain range that runs through the Scandinavian Peninsula. ... The Acadian orogeny is a middle Paleozoic deformation, especially in the northern Appalachians, between Alabama and Newfoundland. ... Illustration of the Taconic orogeny The Taconic orogeny was a great mountain building period that perhaps had the greatest overall effect on the geologic structure of basement rocks within the New York Bight region. ... The Australian continental shelf (light blue) is contiguous with New Guinea, but not with other Pacific islands like New Zealand. ... In the geological timescale, the Ludlow epoch (from 422. ... In the geologic timescale, the Ludfordian is the age of the Ludlow epoch of the Silurian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 421. ... In the geologic timescale, the Gorstian is the age of the Ludlow epoch of the Silurian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 422. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... In the geologic timescale, the Homerian is the second age of the Wenlock epoch of the Silurian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 426. ... In the geologic timescale, the Sheinwoodian is the age of the Wenlock epoch of the Silurian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 428. ... In the geological timescale, the Llandovery epoch (from 443. ... Alexandrian is either: Alexandria Alexandrian text-type This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... In the geologic timescale, the Telychian is the age of the Llandovery epoch of the Silurian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 436. ... Motto: Ut Incepit Fidelis Sic Permanet (Loyal she began, loyal she remains) Other Canadian provinces and territories Capital Toronto Largest city Toronto Lieutenant Governor James K. Bartleman Premier Dalton McGuinty (Liberal) Area 1,076,395 km² (4th)  - Land 917,741 km²  - Water 158,654 km² (14. ... In the geologic timescale, the Aeronian is the age of the Llandovery epoch of the Silurian period of the Paleozoic era of the Fanerozoic eon that is comprehended between 439 million and 436 million years ago, approximatedly. ... In the geologic timescale, the Rhuddanian is the age of the Llandovery epoch of the Silurian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 443. ... Artist impression of the Ordovician Sea. ... The Late Ordovician, also called the Upper Ordovician by geologists, is the third epoch of the Ordovician period. ... The Hirnantian is the seventh and final internationally-recognized stage of the Ordovician Period of the Paleozoic Era. ... Invertebrate is an English word that describes any animal without a spinal column. ... An orthocone is a usually long straight shell of a nautiloid cephalopods. ... Families Orthoceratidae Pseudorthoceratidae and many others Orthocerida are an order of extinct nautiloid cephalopods that lived from the Early Ordovician to the Late Triassic (about 500 to 200 million years ago), but were most common and diverse from the Ordovician to the Devonian. ... Extant Subclasses and Orders Alcyonaria    Alcyonacea    Helioporacea Zoantharia    Antipatharia    Corallimorpharia    Scleractinia    Zoanthidea [1][2]  See Anthozoa for details For other uses, see Coral (disambiguation). ... Diversity About 4000 genera Subphyla and classes See Classification Brachiopods (from Latin bracchium, arm + New Latin -poda, foot) are a nearly extinct, small phylum of benthic invertebrates. ... Subclasses Anomalosdesmata Cryptodonta Heterodonta Paleoheterodonta Palaeotaxodonta Pteriomorphia and see text Mussels in the intertidal zone in Cornwall, England. ... Orders Palcephalopoda †Plectronocerida †Ellesmerocerida †Actinocerida †Pseudorthocerida †Endocerida †Tarphycerida †Oncocerida †Discosorida Nautilida Neocephalopoda (in part) †Orthocerida †Ascocerida †Bactritida Nautiloids are a group of marine mollusks in the subclass Nautiloidea, which all possess an external shell, the best-known example being the modern nautiluses. ... For the robot vacuum cleaner, see Electrolux Trilobite. ... Orders Archaeocopida (extinct) Leperditicopida (extinct) Palaeocopida (extinct) Podocopida Platycopida Myodocopida Introduction Ostracoda is a class of the Crustacea, sometimes known as the seed shrimp because of their appearance. ... Classes Stenolaemata Gymnolaemata Phylactolaemata Bryozoans are tiny colonial animals that generally build stony skeletons of calcium carbonate, superficially similar to coral. ... Classes Asteroidea Concentricycloidea Crinoidea Echinoidea Holothuroidea Ophiuroidea Echinoderms (Echinodermata) is a phylum of marine animals found in the ocean at all depths. ... Subclasses Articulata (540 species) Cladida (extinct) Flexibilia (extinct) Camerata (extinct) Disparida (extinct) Crinoids, also known as sea lilies or feather-stars, are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). ... A database query syntax error has occurred. ... Graptolites (Graptolithina) are fossil colonial animals known chiefly from the Upper Cambrian through the Mississippian (Lower Carboniferous). ... Conodonts are extinct worm-like forms with distinctive conical or multi-denticulate teeth made of apatite (calcium phosphate). ... This article is about the real-life under-sea organisms. ... This article does not cite any references or sources. ... Divisions Non-vascular land plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses †Horneophytopsida Vascular plants (tracheophytes) †Rhyniophyta—rhyniophytes †Zosterophyllophyta—zosterophylls Lycopodiophyta—clubmosses †Trimerophytophyta—trimerophytes Pteridophyta - ferns and horsetails Ophioglossophyta - adders-tongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants The embryophytes... For the fictional character, see Fungus the Bogeyman. ... Artist impression of the Ordovician Sea. ... The Middle Ordovician is the second subdivision of the Ordovician period. ... The Darriwilian faunal stage includes most of the Late Llanwirn. ... Artist impression of the Ordovician Sea. ... The Ordovician period is the second of the six (seven in North America) periods of the Paleozoic era. ... In geology, the Arenig group is the name applied to the lowest stage of the Ordovician System. ... The Tremadocian is the first internationally-recognized stage of the Ordovician Period of the Paleozoic Era. ... For other uses, see Cambrian (disambiguation). ... The Furongian is an geological epoch that is part of the Cambrian Era. ... For other uses, see Cambrian (disambiguation). ... The Cambrian explosion is the geologically kukko sudden appearance in the fossil record of the ancestors of familiar animals, starting about 542 million years ago (Mya). ... Phyla Subkingdom Parazoa Porifera (sponges) Subkingdom Agnotozoa Placozoa Orthonectida Rhombozoa Subkingdom Metazoa Radiata Cnidaria Ctenophora - Comb jellies Bilateria Protostomia Acoelomorpha Platyhelminthes - Flatworms Nemertina - Ribbon worms Gastrotricha Gnathostomulida - Jawed worms Micrognathozoa Rotifera - Rotifers Acanthocephala Priapulida Kinorhyncha Loricifera Entoprocta Nematoda - Roundworms Nematomorpha - Horsehair worms Cycliophora Mollusca - Mollusks Sipuncula - Peanut worms Annelida - Segmented... For other uses, see phyla. ... Typical Classes Subphylum Urochordata - Tunicates Ascidiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... The Archeocyatha, also called Archaeocyathids, were sessile, reef-building marine organisms that lived during the Lower Cambrian period (500-600 million years ago). ... For the robot vacuum cleaner, see Electrolux Trilobite. ... Priapulida (priapulid worms, or penis worms) are a phylum of marine worms with an extensible spiny proboscis. ... The sponge, in the phylum Porifera, is a very primitive and specialized animal. ... Diversity About 4000 genera Subphyla and classes See Classification Brachiopods (from Latin bracchium, arm + New Latin -poda, foot) are a nearly extinct, small phylum of benthic invertebrates. ... Artists reconstruction of an anomalocarid hunting a trilobite. ... Prokaryotic bacteria cell structure Prokaryotes (IPA: //) are a group of organisms that lack a cell nucleus (= karyon), or any other membrane-bound organelles. ... Typical phyla Chromalveolata Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) Cabozoa Excavata Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Archaeplastida (in part) Rhodophyta (red algae) Glaucophyta (basal archaeplastids) Amoebozoa Choanozoa Many others; classification varies Protists (IPA: (RP); (GenAm)), Greek protiston -a meaning the (most) first of all... Orders Allogromiida Carterinida Fusulinida- extinct Globigerinida Involutinida- extinct Lagenida Miliolida Robertinida Rotaliida Silicoloculinida Spirillinida Textulariida incertae sedis    Xenophyophorea    Reticulomyxa The Foraminifera, or forams for short, are a large group of amoeboid protists with reticulating pseudopods, fine strands that branch and merge to form a dynamic net. ... For the fictional character, see Fungus the Bogeyman. ... For the programming language, see algae (programming language). ... For other uses of Gondwana and Gondwanaland, see Gondwana (disambiguation). ... // Overview The Petermann Orogen is an intracontinental event that affected basement rocks of the northern Musgrave Province and Proterozoic sediments of the (now) southern Amadeus Basin between ~550-535 Ma. ... The Australian continental shelf (light blue) is contiguous with New Guinea, but not with other Pacific islands like New Zealand. ... The Adelaide Geosyncline is a major geological province in central South Australia. ... The Australian continental shelf (light blue) is contiguous with New Guinea, but not with other Pacific islands like New Zealand. ... Air redirects here. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... The Holocene epoch is a geological period, which began approximately 11,550 calendar years BP (about 9600 BC) and continues to the present. ... In the geologic timescale, the Paibian is the age of the Furongian epoch of the Cambrian period of the Paleozoic era of the Phanerozoic eon that is comprehended between 501. ... The Ibexian is recognized as the youngest Cambrian and oldest Ordovician series in North America. ... The Middle Cambrian is an geological epoch that is part of the Cambrian Era. ... For other uses, see Cambrian (disambiguation). ... The Early Cambrian is an geological epoch that is part of the Cambrian Era. ... For other uses, see Cambrian (disambiguation). ... The Precambrian (Pre-Cambrian) is an informal name for the supereon comprising the eons of the geologic timescale that came before the current Phanerozoic eon. ... The Proterozoic (IPA: ) is a geological eon representing a period before the first abundant complex life on Earth. ... The Neoproterozoic Era is the unit of geologic time from 1,000 to 542 +/- 0. ... The Ediacaran[5][6]  â€¢  â€¢  | Neoproterozoic (last æon of the Precambrian) Phanerozoic Axis scale: millions of years ago. ... For other uses, see Fossil (disambiguation). ... Phyla Radiata Cnidaria Ctenophora - Comb jellies Bilateria Protostomia Acoelomorpha Platyhelminthes - Flatworms Nemertina - Ribbon worms Gastrotricha Gnathostomulida - Jawed worms Micrognathozoa Rotifera - Rotifers Acanthocephala Priapulida Kinorhyncha Loricifera Entoprocta Nematoda - Roundworms Nematomorpha - Horsehair worms Cycliophora Mollusca - Mollusks Sipuncula - Peanut worms Annelida - Segmented worms Tardigrada - Water bears Onychophora - Velvet worms Arthropoda - Insects, etc. ... Dickinsonia costata, an Ediacaran organism of unknown affinity, with a quilted appearance. ... A fossilized dinosaur footprint at Clayton Lake State Park, New Mexico. ... Trichophycus pedum (or Treptichnus pedum; formerly Phycodes pedum) was one of the earliest animals, and the first found in great abundance. ... The sponge, in the phylum Porifera, is a very primitive and specialized animal. ... Orders Agnostida Redlichiida Corynexochida Lichida Nektaspida? Phacopida Proetida Asaphida Harpetida Ptychopariida Trilobites are extinct arthropods in the class Trilobita. ... Species Dickinsonia is an ancient ovoid fossil with somewhat radial tubes from a (sometimes missing) central ridge. ... Illustration of the Taconic orogeny The Taconic orogeny was a great mountain building period that perhaps had the greatest overall effect on the geologic structure of basement rocks within the New York Bight region. ... North American redirects here. ... This article does not cite any references or sources. ... // Orogeny (Greek for mountain generating) is the process of mountain building, and may be studied as a tectonic structural event, as a geographical event and a chronological event, in that orogenic events cause distinctive structural phenomena and related tectonic activity, affect certain regions of rocks and crust and happen within... Map of South Asia (see note) This article deals with the geophysical region in Asia. ... // Overview The Petermann Orogen is an intracontinental event that affected basement rocks of the northern Musgrave Province and Proterozoic sediments of the (now) southern Amadeus Basin between ~550-535 Ma. ... The Australian continental shelf (light blue) is contiguous with New Guinea, but not with other Pacific islands like New Zealand. ... The Cryogenian Period (from Greek cryos ice and genesis birth) is the second geologic period of the Neoproterozoic Era, followed by the Ediacaran Period. ... One computer simulation of conditions during the Snowball Earth period. ... For other uses, see Fossil (disambiguation). ... In geology, Rodinia (from the Russian родина, or motherland) refers to one of the oldest known supercontinents, which contained most or all of Earths then-current landmass. ... The Tonian (from Greek tonas, stretch) is the first geologic period in the Neoproterozoic Era and lasted from 1000 Ma to 850 Ma (million years ago). ... In geology, Rodinia (from the Russian родина, or motherland) refers to one of the oldest known supercontinents, which contained most or all of Earths then-current landmass. ... A fossilized dinosaur footprint at Clayton Lake State Park, New Mexico. ... Multicellular organisms are those organisms containing more than one cell, and having differentiated cells that perform specialized functions. ... Kingdoms Eukaryotes are organisms with complex cells, in which the genetic material is organized into membrane-bound nuclei. ... Classes Dinophyceae Noctiluciphyceae Syndiniophyceae The dinoflagella are a large group of flagellate protists. ... Acritarchs are small organic structures found as fossils. ... The Grenville orogeny was an episode of mountain-building (orogeny) associated with the assembly of the ancient supercontinent Rodinia. ... A world map showing the continent of Africa Africa is the worlds second-largest and second most-populous continent, after Asia. ... The Gascoyne Comlex is a terrane of granite and migmatite-gneiss which occurs at the northern edge of the Archaean Yilgarn in Western Australia. ... Slogan or Nickname: Wildflower State or the Golden State Other Australian states and territories Capital Perth Government Constitutional monarchy Governor Ken Michael Premier Alan Carpenter (ALP) Federal representation  - House seats 15  - Senate seats 12 Gross State Product (2005-06)  - Product ($m)  $107,910 (4th)  - Product per capita  $53,134/person... The Adelaide Geosyncline is a major geological province in central South Australia. ... The Australian continental shelf (light blue) is contiguous with New Guinea, but not with other Pacific islands like New Zealand. ... The Adelaide Geosyncline is a major geological province in central South Australia. ... The Mesoproterozoic era is a geologic period that occurred between 1600 and 900 million years ago. ... The Stenian (from Greek stenos, narrow) is the final geologic period in the Mesoproterozoic Era and lasted from 1200 million years ago to 1000 million years ago. ... The term Metamorphic can be associated with a number of meanings:- Metamorphic rock The term for rocks that have been transformed by extreme heat and pressure. ... // Orogeny (Greek for mountain generating) is the process of mountain building, and may be studied as a tectonic structural event, as a geographical event and a chronological event, in that orogenic events cause distinctive structural phenomena and related tectonic activity, affect certain regions of rocks and crust and happen within... In geology, Rodinia (from the Russian родина, or motherland) refers to one of the oldest known supercontinents, which contained most or all of Earths then-current landmass. ... The Musgrave Block is an east-west trending belt of Proterozoic granulite-gneiss basement rocks approximately 500km long. ... Central Australia is a term used to describe the area of land surrounding and including Alice Springs in Australia. ... The Ectasian (from Greek ectsis, extension) is the second geologic period in the Mesoproterozoic Era and lasted from 1400 million years ago to 1200 million years ago. ... In geology, a platform cover is the sedimentary and volcanic deposits that lie on top of a craton. ... Divisions Chlorophyta Charophyta Green algae are microscopic protists; found in all aquatic environments, including marine, freshwater and brackish water. ... This is a biological article: For a territory administered by another territory see: Colony For a group attempting to affiliate with a Fraternity or Sorority see: Colony (fraternity) In biology, a colony (from Latin colonia) refers to several individual organisms of the same species living closely together, usually for mutual... The Grenville orogeny was an episode of mountain-building (orogeny) associated with the assembly of the ancient supercontinent Rodinia. ... North American redirects here. ... The Calymmian (from Greek calymma, cover) is the first geologic period in the Mesoproterozoic Era and lasted from 1600 million years ago to 1400 million years ago. ... In geology, a platform cover is the sedimentary and volcanic deposits that lie on top of a craton. ... The term northern Australia is generally considered to include the Australian states and territories of Queensland and the Northern Territory. ... Look up Circa on Wiktionary, the free dictionary The Latin word circa, literally meaning about, is often used to describe various dates (often birth and death dates) that are uncertain. ... The Paleoproterozoic is the first of the three sub-divisions of the Proterozoic occurring between 2500 to 1600 million years ago. ... The Statherian (from Greek statheros, stable, firm) is the final geologic period in the Paleoproterozoic Era and lasted from 1800 million years ago to 1600 million years ago. ... Kingdoms Animalia - Animals Fungi Plantae - Plants Chromalveolata Protista Alternative phylogeny Unikonta Opisthokonta Metazoa Choanozoa Eumycota Amoebozoa Bikonta Apusozoa Cabozoa Rhizaria Excavata Corticata Archaeplastida Chromalveolata Animals, plants, fungi, and protists are eukaryotes (IPA: ), organisms whose cells are organized into complex structures by internal membranes and a cytoskeleton. ... Typical phyla Chromalveolata Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) Cabozoa Excavata Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Archaeplastida (in part) Rhodophyta (red algae) Glaucophyta (basal archaeplastids) Amoebozoa Choanozoa Many others; classification varies Protists (IPA: (RP); (GenAm)), Greek protiston -a meaning the (most) first of all... Slogan or Nickname: Wildflower State or the Golden State Other Australian states and territories Capital Perth Government Constitutional monarchy Governor Ken Michael Premier Alan Carpenter (ALP) Federal representation  - House seats 15  - Senate seats 12 Gross State Product (2005-06)  - Product ($m)  $107,910 (4th)  - Product per capita  $53,134/person... The Gascoyne Comlex is a terrane of granite and migmatite-gneiss which occurs at the northern edge of the Archaean Yilgarn in Western Australia. ... Slogan or Nickname: Wildflower State or the Golden State Other Australian states and territories Capital Perth Government Constitutional monarchy Governor Ken Michael Premier Alan Carpenter (ALP) Federal representation  - House seats 15  - Senate seats 12 Gross State Product (2005-06)  - Product ($m)  $107,910 (4th)  - Product per capita  $53,134/person... For the song, see South Australia (song). ... The Orosirian (from Greek orosira, mountain range) is the third geologic period in the Paleoproterozoic Era and lasted from 2050 million years ago to 1800 million years ago. ... Air redirects here. ... This article is about the chemical element and its most stable form, or dioxygen. ... Vredefort crater is the largest verified impact crater on Earth. ... This article or section does not cite any references or sources. ... // Orogeny (Greek for mountain generating) is the process of mountain building, and may be studied as a tectonic structural event, as a geographical event and a chronological event, in that orogenic events cause distinctive structural phenomena and related tectonic activity, affect certain regions of rocks and crust and happen within... The Trans-Hudsonian orogeny was a major orogenic event in North America during the Proterozoic. ... The Australian continental shelf (light blue) is contiguous with New Guinea, but not with other Pacific islands like New Zealand. ... Look up Circa on Wiktionary, the free dictionary The Latin word circa, literally meaning about, is often used to describe various dates (often birth and death dates) that are uncertain. ... Basic geological regions of Australia, by age. ... From the GeoWhen Database: Rhyacian Period From 2300 +/- 0 To 2050 +/- 0 Ma Start Defined By: Fixed Date End Defined By: Fixed Date Start Based On: Gradstein, Ogg, Smith, et. ... The Bushveld is a geographic region of South Africa that encompasses most of Limpopo Province and part of the North West Province. ... The Huronian glaciation was from 2400 mya to 2100 mya, during the Siderian and Rhyacian periods of the Paleoproterozoic era. ... The Siderian (from Greek sideros, iron) is the first geologic period in the Paleoproterozoic Era and lasted from 2500 million years ago to 2300 million years ago. ... The Oxygen Catastrophe was a massive environmental change believed to have happened during the Siderian period at the beginning of the Paleoproterozoic era. ... 2. ... The Australian continental shelf (light blue) is contiguous with New Guinea, but not with other Pacific islands like New Zealand. ... Basic geological regions of Australia, by age. ... The Archean is a geologic eon; it is a somewhat antiquated term for the time span between 2500 million years before the present and 3800 million years before the present. ... The Neoarchean is a geologic era within the Archaean. ... World geologic provinces. ... Earth cutaway from core to exosphere. ... The Abitibi greenstone belt is a 2,800-2,600 million year old greenstone belt that spans across the Ontario-Quebec border in Canada. ... This article is about the Canadian province. ... This article is about the Canadian province. ... The Mesoarchean is a geologic era within the Archean, spanning 3. ... Pre-Cambrian stromatolites in the Siyeh Formation, Glacier National Park. ... This is a biological article: For a territory administered by another territory see: Colony For a group attempting to affiliate with a Fraternity or Sorority see: Colony (fraternity) In biology, a colony (from Latin colonia) refers to several individual organisms of the same species living closely together, usually for mutual... Orders The taxonomy is currently under revision. ... Plant macrofossils are preserved remains large enough to be visible without a microscope. ... The Blake River Megacaldera Complex, also called the Blake River Group, is a giant subaqueous 2707-2696 million year old caldera cluster or a nested caldera system that spans across the Ontario-Quebec border in Canada. ... This article is about the Canadian province. ... This article is about the Canadian province. ... The Paleoarchean is a geologic era within the Archaean. ... Phototrophs or photoautotrophs are photosynthetic algae, fungi, bacteria and cyanobacteria which build up carbon dioxide and water into organic cell materials using energy from sunlight. ... Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ... For other uses of the term, see Fossil (disambiguation) Fossils are the mineralized remains of animals or plants or other artifacts such as footprints. ... World geologic provinces. ... Canadian Shield Canadian Shield Landform. ... The Pilbara craton (the Pilbara province in northwest Western Australia), along with the Kaapvaal craton (the Kaapvaal province of South Africa) are the only remaining areas of pristine Archaean 3. ... In the geologic timescale, the Eoarchean or EA was an era that lasted from about 3800 MYA to 3600 MYA. It is the first part of the Archaean eon and the first part of the Precambrian eon. ... Prokaryotic bacteria cell structure Prokaryotes (IPA: //) are a group of organisms that lack a cell nucleus (= karyon), or any other membrane-bound organelles. ... Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ... Phyla Crenarchaeota Euryarchaeota Korarchaeota Nanoarchaeota ARMAN The Archaea (pronounced ) are a group of prokaryotic and single-celled microorganisms. ... For other uses of the term, see Fossil (disambiguation) Fossils are the mineralized remains of animals or plants or other artifacts such as footprints. ... The name Hadean refers to the geologic period before 3800 million years ago (mya). ... In the Lunar geologic timescale, the Lower Imbrian epoch occurred between 3850 million years ago to about 3800 million years ago. ... The Late Heavy Bombardment (LHB) was a period approximately 3. ... An inner planet is any one of the Solar systems rocky planets that lie inside the asteroid belt: Mercury (planet), Venus (planet), Earth (planet) and Mars (planet). ... This article is about the Solar System. ... The Nectarian Period of the lunar geologic timescale runs from 3920 million years ago to 3850 million years ago. ... The lunar geologic timescale (or perhaps more properly the selenologic timescale) divides the history of Earths Moon into six generally recognized geologic periods: Copernician Period : 1100 MY to present Eratosthenian Period : 3200 MY to 1100 MY Upper Imbrian Epoch : 3800 MY to 3200 MY Lower Imbrian Epoch : 3850 MY... Mare Nectaris (the sea of nectar) is a lunar mare located within the Nectaris basin on the lunar nearside. ... Artists impression of a major impact event. ... The Basin Groups of the lunar geologic timescale runs from 4150 million years ago to 3920 million years ago. ... Lifeform is the physical entity which encompasses a life. ... Self-replication is the process by which some things make copies of themselves. ... For other uses, see RNA (disambiguation). ... 3D (left and center) and 2D (right) representations of the terpenoid molecule atisane. ... Cryptic era occoured from 4. ... For other uses, see Mineral (disambiguation). ... Zircon is a mineral belonging to the group of nesosilicates. ... Annum is a Latin noun meaning year. ... This article is about Earth as a planet. ... Title page of the 3rd ed. ... Faunal stages are a subdivision of geologic time used primarily by paleontologists who study fossils rather than by geologists who study rock formations. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ... is the 78th day of the year (79th in leap years) in the Gregorian calendar. ... Radiometric dating (often called radioactive dating) is a technique used to date materials, based on a comparison between the observed abundance of particular naturally occurring radioactive isotopes and their known decay rates. ... The International Commission on Stratigraphy concerns itself with stratigraphy on a global scale. ... A Global Boundary Stratotype Section and Point, abbreviated GSSP, is an internationally agreed upon stratigraphic section which serves as the reference section for a particular boundary on the geologic timescale. ... This is a list of Global Boundary Stratotype Sections and Points. ... Mammals are the dominant creatures of Cenozoic. ... The Quaternary Period is the geologic time period from the end of the Pliocene Epoch roughly 1. ... Tertiary geological time interval covers roughly the time span between the demise of the non-avian dinosaurs and beginning of the most recent Ice Age, approximately 65 million to 1. ... Neogene Period is a unit of geologic time consisting of the Miocene, Pliocene, Pleistocene, and Holocene epochs. ... Paleogene (alternatively Palaeogene) period is a unit of geologic time that began 65 and ended 23 million years ago. ... Air redirects here. ... Carbon dioxide (chemical formula: ) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. ... Carbon dioxide in the Earths atmosphere is present in a low concentration. ... Image File history File links Phanerozoic_Carbon_Dioxide. ... Image File history File links // Description Expanded view of climate change during the last five million years, showing the rapid oscillations in the glacial state. ... Description Expansion of changes during the recent sequence of glacials and interglacials This figure shows the climate record of Lisiecki and Raymo (2005) [1] constructed by combining measurements from 57 globally distributed deep sea sediment cores. ... The Holocene epoch is a geological period, which began approximately 11,550 calendar years BP (about 9600 BC) and continues to the present. ... The Upper Paleolithic (or Upper Palaeolithic) is the third and last subdivision of the Paleolithic or Old Stone Age as it is understood in Europe, Africa and Asia. ... Before Present (BP) years are the units of time (counted backwards to the past) used to report raw radiocarbon ages and dates referenced to the BP scale origin in the year AD 1950 (identical to 1950 CE). ... The Holocene epoch is a geological period, which began approximately 11,550 calendar years BP (about 9600 BC) and continues to the present. ... “Mississippian” redirects here. ... The Pennsylvanian is an epoch of the Carboniferous period lasting from roughly 325 Ma to 299 Ma (million years ago). ... The Precambrian (Pre-Cambrian) is an informal name for the supereon comprising the eons of the geologic timescale that came before the current Phanerozoic eon. ... The Proterozoic (IPA: ) is a geological eon representing a period before the first abundant complex life on Earth. ... The Archean is a geologic eon; it is a somewhat antiquated term for the time span between 2500 million years before the present and 3800 million years before the present. ... The name Hadean refers to the geologic period before 3800 million years ago (mya). ... The Precambrian (Pre-Cambrian) is an informal name for the supereon comprising the eons of the geologic timescale that came before the current Phanerozoic eon. ... A Global Standard Stratigraphic Age, often abbreviated GSSA, is an internationally agreed upon chronological age used to define the boundaries between different periods or epochs on the geologic timescale. ... World geologic provinces. ... The thickness of the Earths crust (km). ... The name Hadean refers to the geologic period before 3800 million years ago (mya). ... The lunar geologic timescale divides the history of Earths moon into five generally recognized geologic periods: the Copernican, Eratosthenian, Imbrian (upper and lower), Nectarian, and Pre-Nectarian. ... Cryptic era occoured from 4. ... The Basin Groups of the lunar geologic timescale runs from 4150 million years ago to 3920 million years ago. ... The Pre-Nectarian Period of the lunar geologic timescale runs from 4550 million years ago (the time of the initial formation of the Moon) to 3920 million years ago, when the Nectaris Basin was formed by a large impact. ... The Nectarian Period of the lunar geologic timescale runs from 3920 million years ago to 3850 million years ago. ... In the Lunar geologic timescale, the Lower Imbrian epoch occurred between 3850 million years ago to about 3800 million years ago. ... The lunar geologic timescale (or perhaps more properly the selenologic timescale) divides the history of Earths Moon into six generally recognized geologic periods: Copernician Period : 1100 MY to present Eratosthenian Period : 3200 MY to 1100 MY Upper Imbrian Epoch : 3800 MY to 3200 MY Lower Imbrian Epoch : 3850 MY... The Acasta Gneiss is a rock outcrop of Archaean tonalite gneiss in the Northwest Territories, Canada. ... For the former United States territory, see Northwest Territory. ...

References and footnotes

See also

Earth as seen from Apollo 17 Modern geologists consider the age of the Earth to be around 4. ... The term Anthropocene is used by some scientists to describe the most recent period in the Earths history, starting in the 18th century where the activities of the human race first began to have a significant global effect on the Earths climate and ecosystems. ... This timeline attempts to show the best scientific estimates of the timings of past events and predictions of the approximate timing of hypothetical future events with cosmological significance. ... Deep time is the theory that Earth is billions of years old and thus had a long history of development and change. ... Geological time scale. ... Geological time put in a diagram called a geological clock, showing the relative lengths of the eons of the Earths history. ... List of fossil sites: // ^ http://www. ... A logarithmic timeline, based on logarithmic scale, was developed by Heinz von Foerster, the philosopher and physicist. ... The lunar geologic timescale (or perhaps more properly the selenologic timescale) divides the history of Earths Moon into six generally recognized geologic periods: Copernician Period : 1100 MY to present Eratosthenian Period : 3200 MY to 1100 MY Upper Imbrian Epoch : 3800 MY to 3200 MY Lower Imbrian Epoch : 3850 MY... The Martian geologic timescale has three broad epochs defined by the number of impact craters on the surface; older surfaces have more craters. ... Table of natural history, 1728 Cyclopaedia Natural history is an umbrella term for what are now often viewed as several distinct scientific disciplines of integrative organismal biology. ... Life on Earth  â€¢  â€¢  | Axis scale: millions of years ago. ... This article does not cite any references or sources. ... This time line of the geologic history of the United States chronologically lists important events occurring within the present political boundaries of United States (including territories) before 12,000 years ago. ... // This is a timeline of geological and relevant astronomical events on Earth before the Cambrian period started. ...

External links

• NASA: Geologic Time
• GSA: Geologic Time Scale
• British Geological Survey: Geological Timechart
• GeoWhen Database
• International Commission on Stratigraphy Time Scale
• CHRONOS
• National Museum of Natural History - Geologic Time
• SeeGrid: Geological Time Systems Information model for the geologic time scale
• Exploring Time from Planck Time to the lifespan of the universe

v • d • e   Time   Major concepts Time · Eternity · Arguments for eternity · Immortality Deep time · History · Past · Present · Future · Futurology Time Portal Measurement and Standards Chronometry · UTC · UT · TAI · Second · Minute · Hour · Sidereal time · Solar time · Time zone Clock · Horology · History of timekeeping devices · Astrarium · Marine chronometer · Sundial · Water clock This article is about the concept of time. ... This article is about the concept of time. ... While in the popular mind, eternity often simply means existing for an infinite, i. ... Arguments for eternity composed a particularly important area of philosophical debate among Greek, Jewish, Islamic, and Christian philosophers during the ancient and medieval periods. ... The Fountain of Eternal Life in Cleveland, Ohio Immortality (or eternal life) is the concept of living in physical or spiritual form for an infinite length of time, or in a state of timelessness. ... Deep time is the theory that Earth is billions of years old and thus had a long history of development and change. ... HIStory – Past, Present and Future, Book I is a double album by American singer Michael Jackson released in June 1995 and remains Jacksons most conflicting and controversial release. ... The past is the portion of the timeline that has already occurred; it is the opposite of the future. ... Present redirects here. ... For other uses, see Future (disambiguation). ... Futurology is the detailed critical inspection and reasoning of the state in which things will develop in the future on the basis of existing circumstances in history. ... Image File history File links Portal. ... A time scale specifies divisions of time. ... Wikipedia does not yet have an article with this exact name. ... UTC redirects here. ... Universal Time (UT) is a timescale based on the rotation of the Earth. ... International Atomic Time (TAI, from the French name Temps Atomique International) is a high-precision atomic time standard that tracks proper time on Earths geoid. ... This article is about the unit of time. ... This article is about the unit of time, angle and right ascension. ... The hour (symbol: h) is a unit of time. ... Sidereal time is time measured by the apparent diurnal motion of the vernal equinox, which is very close to, but not identical with, the motion of stars. ... Solar time is based on the idea that when the sun reaches its highest point in the sky, it is noon. ... Timezone and TimeZone redirect here. ... For other uses, see Clock (disambiguation). ... Horology is the study of the science and art of timekeeping devices. ... An astrarium, also called a planetarium, is the mechanical representation of the cyclic nature of astronomical objects in one timepiece. ... A marine chronometer is a timekeeper precise enough to be used as a portable time standard, used to determine longitude by means of celestial navigation. ... For other uses, see Sundial (disambiguation). ... A water clock or clepsydra is a device for measuring time by letting water regularly flow out of a container usually by a tiny aperture. ... Calendar · Day · Week · Month · Year · Tropical year · Julian · Gregorian · Islamic For other uses, see Calendar (disambiguation) A page from the Hindu calendar 1871–1872. ... Look up day in Wiktionary, the free dictionary. ... For more details on each day of the week, see days of the week. ... Look up Month in Wiktionary, the free dictionary. ... A year (from Old English gÄ“r) is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... A tropical year is the length of time that the Sun, as viewed from the Earth, takes to return to the same position along the ecliptic (its path among the stars on the celestial sphere). ... The Julian calendar was a reform of the Roman calendar which was introduced by Julius Caesar in 46 BC and came into force in 45 BC (709 ab urbe condita). ... For the calendar of religious holidays and periods, see liturgical year. ... The Islamic calendar or Muslim calendar (Arabic: التقويم الهجري; at-taqwÄ«m al-hijrÄ«; Persian: تقویم هجري قمری ‎ taqwÄ«m-e hejri-ye qamari; also called the Hijri calendar) is the calendar used to date events in many predominantly Muslim countries, and used by Muslims everywhere to determine the proper day on which to celebrate...   Intercalation · Leap second · Leap year Chronology Astronomical chronology · Geologic Time · Geological history · Geochronology · Archaeological dating Calendar era · Regnal year · Chronicle · Timeline · Periodization Religion and Mythology Time and fate deities · Wheel of time · Kāla · Kalachakra · Prophecy · Dreamtime Philosophy Causality · Eternalism · Eternal return · Event · The Unreality of Time · A-series and B-series · B-Theory of time Endurantism · Four dimensionalism · Perdurantism · Presentism · Temporal finitism · Temporal parts Physical Sciences Time in physics · Spacetime · Absolute time and space · T-symmetry Arrow of time · Chronon · Fourth dimension · Planck epoch · Planck time · Time domain Intercalation is the insertioffn of an extra day, week or month into some calendar years to make the calendar follow the seasons. ... A leap second is a one-second adjustment to civil time in order to keep it close to the mean solar time. ... For the 1921 film starring Fatty Arbuckle, see Leap Year (film). ... For the novel by Michael Crichton, see Timeline (novel). ... Geological time scale. ... Geochronology is the science of determining the age of rocks, fossils, and sediments. ... Dating material drawn from the archaeological record can made by a direct study of a artifact or may be deduced by association with materials found in the context the item is drawn from or inferred by its point of discovery in the sequence relative to datable contexts. ... A calendar era is the year numbering system used by a calendar. ... Regnal year: the year of the reign of a sovereign. ... Generally a chronicle (Latin chronica, from Greek Χρόνος) is historical account of facts and events in chronological order. ... For other uses, see Timeline (disambiguation). ... Periodization is the attempt to categorize or divide time into discrete named blocks. ... Wheel of time may refer to: The Wheel of time or history, a religious concept predominant in Buddhism and Hinduism The Wheel of Time, a fantasy book series by author Robert Jordan The Wheel of Time (computer game), an action first-person shooter based on the series The Timewheel, a... is the Sanskrit for time (from a root to enumerate; unrelated to black whence ). It denotes a fixed or right point in time (compare rtu, kairos). ... Kālacakra (Sanskrit कालचक्र; Tibetan དུས་ཀྱི་འཁོར་ལོ་ dus kyi khor lo) is a term used in Tantric Buddhism that means time-wheel or time-cycles. It refers both to a Tantric deity (Tib. ... For other uses, see Prophecy (disambiguation). ... opens chapter nine of The Dreaming Universe (1994) entitled The Dreamtime with a quote from The Last Wave, a film by Peter Weir: Aboriginals believe in two forms of time. ... Philosophy of space and time is the branch of philosophy concerned with the issues surrounding the ontology, epistemology, and character of space and time. ... Causality or causation denotes the relationship between one event (called cause) and another event (called effect) which is the consequence (result) of the first. ... Eternalism is a philosophical approach to the ontological nature of time. ... Eternal return or sometimes eternal recurrence is a concept originating from ancient Egypt and developed in the teachings of Pythagoras. ... This page is a candidate for speedy deletion because: this page is a test If you disagree with its speedy deletion, please explain why on its talk page or at Wikipedia:Speedy deletions. ... Wikisource has original text related to this article: The Unreality of Time To meet Wikipedias quality standards, this article or section may require cleanup. ... A-series and B-series are terms introduced by the Scottish idealist philosopher John McTaggart in 1908 which have become classic terms of reference in modern discussions of the philosophy of time, even outside the analytic tradition. ... The B-theory of time is a term, given to one a two positions taken by theorists, in the philosophy of time. ... This article or section is in need of attention from an expert on the subject. ... In the philosophy of time, four dimensionalism is the view that reality is a four-dimensional continuum composed of time and space (spacetime). ... Perdurantism or perdurance theory is a philosophical theory of persistence and identity. ... In the philosophy of time, presentism is the belief that neither the future nor the past exists. ... Temporal Parts are used in contemporary metaphysics in the debate over persistence of material objects. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... For other uses of this term, see Spacetime (disambiguation). ... In physics, the concept of absolute time and absolute space are hypothetical models in which time either runs at the same rate for all the observers in the universe or the rate of time of each observer can be scaled to the absolute time by multiplying the rate by a... T-symmetry is the symmetry of physical laws under a time-reversal transformation— The universe is not symmetric under time reversal, although in restricted contexts one may find this symmetry. ... This article or section does not cite its references or sources. ... A chronon is a hypothetical concept in theoretical physics intended to describe a quantum of time. ... For other uses, see Fourth dimension (disambiguation). ... Named after Max Planck, in cosmology the Planck epoch (or Planck Era) is the earliest period of time in the history of the universe, from zero to 10-43 seconds (one Planck time), during which all four fundamental forces were unified and elementary particles did not yet exist. ... In physics, the Planck time (tP), is the unit of time in the system of natural units known as Planck units. ... Time-domain is a term used to describe the analysis of mathematical functions, or real-life signals, with respect to time. ... Theory of relativity · Time dilation · Gravitational time dilation · Coordinate time · Proper time Psychology Consciousness and spacetime · Mental chronometry · Reaction time · Sense of time · Specious present Sociology and Anthropology Futures studies · Long Now Foundation · Time discipline · Time use research Economics Newtonian time in economics · Time value of money Related topics Space · Duration · Time capsule · Time travel · Time signature · System time · Carpe diem · Tempus fugit

v • d • e Time measurement and standards Major subjects Time · Chronometry · Orders of magnitude · Units of time · Metrology Time Portal International standards UTC · UT · TAI · ISO 31-1 · Second · DUT1 · Leap second · IERS Terrestrial Time · Geocentric Coordinate Time · Barycentric Coordinate Time -1... Time dilation is the phenomenon whereby an observer finds that anothers clock which is physically identical to their own is ticking at a slower rate as measured by their own clock. ... Gravitational time dilation is a consequence of Albert Einsteins theories of relativity and related theories which causes time to pass at different rates in regions of a different gravitational potential; the higher the local distortion of spacetime due to gravity, the slower time passes. ... Coordinate time is the interval of time independent of relativistic time dilation. ... In relativity, proper time is time measured by a single clock between events that occur at the same place as the clock. ... Space-time theories of consciousness relate the geometrical features of conscious experience, such as viewing things in space-time at a point, to the geometrical properties of the universe itself. ... // Definition and history Psychologists have investigated mental chronometry for over 100 years. ... Reaction time (RT) is the elapsed time between the presentation of a sensory stimulus and the subsequent behavioral response. ... Although the sense of time is not associated with a specific sensory system, the work of psychologists and neuroscientists indicates that our brains do have a system governing the perception of time. ... The specious present is the time duration wherein ones perceptions are considered to be in the present. ... Future studies reflects on how today’s changes (or the lack thereof) become tomorrow’s reality. ... The Long Now Foundation, established in 1996, is a private organization that seeks to become the seed of a very long-term cultural institution. ... In sociology and anthropology, time discipline is the general name given to social and economic rules, conventions, customs, and expectations governing the measurement of time, the social currency and awareness of time measurements, and peoples expectations concerning the observance of these customs by others. ... Time use research is a developing interdisciplinary field of study dedicated to knowing how people allocate their time during an average day. ... The time value of money is the premise that an investor prefers to receive a payment of a fixed amount of money today, rather than an equal amount in the future, all else being equal. ... This article is about the idea of space. ... A duration is an amount of time or a particular time interval. ... For other uses, see Time capsule (disambiguation). ... Time travel is a concept that has long fascinated humanity—whether it is Merlin experiencing time backwards, or religious traditions like Mohammeds trip to Jerusalem and ascent to heaven, returning before a glass knocked over had spilt its contents. ... The time signature (also known as meter signature) is a notational convention used in Western musical notation to specify how many beats are in each measure and what note value constitutes one beat. ... In computer science and computer programming, system time represents a computer systems notion of the passing of time. ... For other uses, see Carpe diem (disambiguation). ... Tempus fugit on a sundial Tempus fugit is a Latin expression meaning time flees, more commonly translated as time flies. It is frequently used as an inscription on clocks. ... A time scale specifies divisions of time. ... This article is about the concept of time. ... Wikipedia does not yet have an article with this exact name. ... // The pages linked in the right-hand column contain lists of times that are of the same order of magnitude (power of ten). ... Metrology (from Greek metron (measure), and -logy) is the science of measurement. ... Image File history File links Portal. ... UTC redirects here. ... Universal Time (UT) is a timescale based on the rotation of the Earth. ... International Atomic Time (TAI, from the French name Temps Atomique International) is a high-precision atomic time standard that tracks proper time on Earths geoid. ... ISO 31-1 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to space and time. ... This article is about the unit of time. ... The time correction DUT1 is the difference between the Universal Time scale UT1 (which corresponds to the Earths rotation) and the Coordinated Universal Time (UTC) (which corresponds, except for a constant offset, to International Atomic Time (TAI)). DUT1 = UT1 - UTC DUT1 is maintained in the range -0. ... A leap second is a one-second adjustment to civil time in order to keep it close to the mean solar time. ... The International Earth Rotation and Reference Systems Service is the body responsible for maintaining global time and reference frame standards, notably through its Earth Orientation Parameter (EOP) and International Celestial Reference System (ICRS) groups. ... Terrestrial Time (TT) is the modern time standard for time on the surface of the Earth. ... Geocentric Coordinate Time (TCG) is a coordinate time standard intended to be used as the independent variable of time for all calculations pertaining to precession, nutation, the Moon, and artificial satellites of the Earth. ... Barycentric Coordinate Time (TCB) was defined in 1991 by the International Astronomical Union as one of the replacements for the ill-defined Barycentric Dynamical Time (TDB). ... Civil time · Minute · Hour · 12-hour clock · 24-hour clock · ISO 8601 Civil time is another name for mean solar time reckoned from midnight. ... This article is about the unit of time, angle and right ascension. ... The hour (symbol: h) is a unit of time. ... The 12-hour clock is a timekeeping convention in which the 24 hours of the day are divided into two periods called ante meridiem (a. ... The 24-hour clock is a convention of time keeping in which the day runs from midnight to midnight and is divided into 24 hours, numbered from 0 to 23. ... ISO 8601 is an international standard for date and time representations issued by the International Organization for Standardization (ISO). ... International Date Line · Solar time · Time zone · Daylight saving time · Time offset · Annum Obsolete standards Ephemeris time · Barycentric Dynamical Time · Greenwich Mean Time · Prime Meridian Time in physics Spacetime · Chronon · Cosmological decade · Planck epoch · Planck time · T-symmetry Theory of relativity · Time dilation · Gravitational time dilation · Coordinate time · Proper time “Date line” redirects here. ... Solar time is based on the idea that when the sun reaches its highest point in the sky, it is noon. ... Timezone and TimeZone redirect here. ... Although DST is common in Europe and North America, most of the worlds people do not use it. ... A time offset is defined by international convention as a number of hours and minutes from Coordinated Universal Time in Greenwich, England. ... Annum is a Latin noun meaning year. ... Ephemeris Time (ET) is a now obsolete time scale used in ephemerides of celestial bodies, in particular the Sun (as observed from the Earth), Moon, planets, and other members of the solar system. ... Barycentric Dynamical Time (TDB) was defined by the International Astronomical Union (IAU) in 1976 to be used as the relativistic replacement for the non-relativistic Ephemeris Time which had been used in the ephemerides starting in 1960. ... GMT redirects here. ... Location of the Prime Meridian Image:Prime Meridian. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... For other uses of this term, see Spacetime (disambiguation). ... A chronon is a hypothetical concept in theoretical physics intended to describe a quantum of time. ... A cosmological decade ( CÐ ) is a division of the lifetime of the cosmos. ... Named after Max Planck, in cosmology the Planck epoch (or Planck Era) is the earliest period of time in the history of the universe, from zero to 10-43 seconds (one Planck time), during which all four fundamental forces were unified and elementary particles did not yet exist. ... In physics, the Planck time (tP), is the unit of time in the system of natural units known as Planck units. ... T-symmetry is the symmetry of physical laws under a time-reversal transformation— The universe is not symmetric under time reversal, although in restricted contexts one may find this symmetry. ... -1... Time dilation is the phenomenon whereby an observer finds that anothers clock which is physically identical to their own is ticking at a slower rate as measured by their own clock. ... Gravitational time dilation is a consequence of Albert Einsteins theories of relativity and related theories which causes time to pass at different rates in regions of a different gravitational potential; the higher the local distortion of spacetime due to gravity, the slower time passes. ... Coordinate time is the interval of time independent of relativistic time dilation. ... In relativity, proper time is time measured by a single clock between events that occur at the same place as the clock. ... Time domain · Continuous time · Discrete time · Absolute time and space Horology Clock · Astrarium · Atomic clock · Hourglass · Marine chronometer · Radio clock · Sundial · Watch · Water clock History of timekeeping devices · Equation of time · Complication Calendar Day · Week · Month · Year · Decade · Century · Millennium Astronomical · Julian · Gregorian · Islamic · Lunisolar · Solar · Lunar · Epact · Intercalation · Leap year Time-domain is a term used to describe the analysis of mathematical functions, or real-life signals, with respect to time. ... A continuous signal or a continuous time signal is a varying quantity (a signal) that can be, or is expressed, as a continuous function of an independent variable, usually time. ... Discrete time is non-continuous time. ... In physics, the concept of absolute time and absolute space are hypothetical models in which time either runs at the same rate for all the observers in the universe or the rate of time of each observer can be scaled to the absolute time by multiplying the rate by a... Horology is the study of the science and art of timekeeping devices. ... For other uses, see Clock (disambiguation). ... An astrarium, also called a planetarium, is the mechanical representation of the cyclic nature of astronomical objects in one timepiece. ... “Nuclear Clock” redirects here. ... For other uses, see Hourglass (disambiguation). ... A marine chronometer is a timekeeper precise enough to be used as a portable time standard, used to determine longitude by means of celestial navigation. ... A radio clock A radio clock is a clock that is synchronized by a time code bit stream transmitted by a radio transmitter connected to a time standard such as an atomic clock. ... For other uses, see Sundial (disambiguation). ... For other uses, see Watch (disambiguation). ... A water clock or clepsydra is a device for measuring time by letting water regularly flow out of a container usually by a tiny aperture. ... The equation of time is the difference, over the course of a year, between time as read from a sundial and a clock. ... In horology terms, a complication in a mechanical timepiece is any feature beyond that of a simple hours, minutes, and seconds movement. ... For other uses, see Calendar (disambiguation) A page from the Hindu calendar 1871–1872. ... Look up day in Wiktionary, the free dictionary. ... For more details on each day of the week, see days of the week. ... Look up Month in Wiktionary, the free dictionary. ... A year (from Old English gÄ“r) is the time between two recurrences of an event related to the orbit of the Earth around the Sun. ... For other senses of this word, see decade (disambiguation). ... A century (From the Latin cent, one hundred) is one hundred consecutive years. ... A millennium (pl. ... Astronomical year numbering is based on BCE/CE (or BC/AD) year numbering, but follows normal decimal integer numbering more strictly. ... The Julian calendar was a reform of the Roman calendar which was introduced by Julius Caesar in 46 BC and came into force in 45 BC (709 ab urbe condita). ... For the calendar of religious holidays and periods, see liturgical year. ... The Islamic calendar or Muslim calendar (Arabic: التقويم الهجري; at-taqwÄ«m al-hijrÄ«; Persian: تقویم هجري قمری ‎ taqwÄ«m-e hejri-ye qamari; also called the Hijri calendar) is the calendar used to date events in many predominantly Muslim countries, and used by Muslims everywhere to determine the proper day on which to celebrate... A lunisolar calendar is a calendar whose date indicates both the moon phase and the time of the solar year. ... A solar calendar is a calendar whose dates indicate the position of the earth on its revolution around the sun (or equivalently the apparent position of the sun moving on the celestial sphere). ... A lunar calendar is a calendar that is based on cycles of the moon phase. ... The epact (from Greek: epaktai hèmerai = added days) is, as the second Canon of the Gregorian Calendar reform puts it, nothing else than the number of days which the common solar year of 365 days surpasses the common lunar year of 354 days (Latin: Epacta nihil aliud est quam... Intercalation is the insertioffn of an extra day, week or month into some calendar years to make the calendar follow the seasons. ... For the 1921 film starring Fatty Arbuckle, see Leap Year (film). ... Tropical year · Equinox · Solstice · Days of the week · Calculating the day of the week · Dominical letter Archaeology & geology International Commission on Stratigraphy · Geologic Time · Archaeological dating Astronomical chronology Nuclear time scale · Precession · Sidereal time · Galactic year Unusual units Fortnight · Jiffy · Lustrum · Saeculum · Shake · Tide Related topics Chronology · Duration · System time · Mental chronometry · Time value of money · Timekeeper

v • d • e Chronology Major subjects Time · Astronomy · Geology · Paleontology · Archaeology · History Time Portal Eras and Epochs Calendar Eras: Ab urbe condita · Anno Domini / Common Era · Anno Mundi · Spanish era · Before Present · Hijri Egyptian · Sothic cycle · Hindu units of measurement · Hindu Yugas A tropical year is the length of time that the Sun, as viewed from the Earth, takes to return to the same position along the ecliptic (its path among the stars on the celestial sphere). ... For other uses, see Equinox (disambiguation). ... “Summer solstice” redirects here. ... This article is about days of the week. ... This article details various mathematical algorithms to calculate the day of the week for any particular date in the past or future. ... The days of the year are sometimes designated letters A, B, C, D, E, F and G in a cycle of 7 as an aid for finding the day of week of a given calendar date and in calculating Easter. ... The International Commission on Stratigraphy concerns itself with stratigraphy on a global scale. ... Dating material drawn from the archaeological record can made by a direct study of a artifact or may be deduced by association with materials found in the context the item is drawn from or inferred by its point of discovery in the sequence relative to datable contexts. ... The precession of Earths axis of rotation with respect to inertial space is also called the precession of the equinoxes. ... Sidereal time is time measured by the apparent diurnal motion of the vernal equinox, which is very close to, but not identical with, the motion of stars. ... // Galactic time NGC 4414, a typical spiral galaxy alike our Milky Way Galactic time, not to confuse with siderial time, is the time that is described by our spin relative to the center of the galaxy. ... Look up fortnight in Wiktionary, the free dictionary. ... The term jiffy (or jiffie) is used in different applications for various different short periods of time, usually 1/60 of a second. ... Lustrum was a sacrifice for expiation and purification offered by one of the censors of Rome in name of the Roman people at the close of the taking of the census, and which took place after a period of five years, so that the name came to denote a period... A saeculum is a length of time roughly equal to the lifetime of a person, or about 90 years. ... A shake is an informal unit of time equal to 10 nanoseconds, or 10-8 seconds. ... A tide is an obsolete or archaic term for time, period or season, such as eventide, shrovetide, Eastertide, etc. ... For the novel by Michael Crichton, see Timeline (novel). ... A duration is an amount of time or a particular time interval. ... In computer science and computer programming, system time represents a computer systems notion of the passing of time. ... // Definition and history Psychologists have investigated mental chronometry for over 100 years. ... The time value of money is the premise that an investor prefers to receive a payment of a fixed amount of money today, rather than an equal amount in the future, all else being equal. ... Look up timekeeper in Wiktionary, the free dictionary. ... For the novel by Michael Crichton, see Timeline (novel). ... This article is about the concept of time. ... For other uses, see Astronomy (disambiguation). ... This article includes a list of works cited but its sources remain unclear because it lacks in-text citations. ... Paleontology, palaeontology or palæontology (from Greek: paleo, ancient; ontos, being; and logos, knowledge) is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. ... For referencing in Wikipedia, see Wikipedia:Citing sources. ... HIStory – Past, Present and Future, Book I is a double album by American singer Michael Jackson released in June 1995 and remains Jacksons most conflicting and controversial release. ... Image File history File links Download high resolution version (800x697, 123 KB) fr:: Montre gousset cs:: Kapesní hodinky de: Deutsch: Taschenuhr en: English: Pocket watch it: Italiano: Orologio da taschino (cipolla) es: Español: Reloj de bolsillo Template:ગુજરાતી ગુજરાતી: ખિસ્સામાં રાખવાની ઘડિયાળ ja: 日本語: 懐中時計 pl: Polski: Zegarek kieszonkowy pt: Português: Relógio de bolso... Image File history File links Portal. ... An era is a long period of time with different technical and colloquial meanings, and usages in language. ... In chronology, an epoch (or epochal date, or epochal event) means an instant in time chosen as the origin of a particular era. ... A calendar era is the year numbering system used by a calendar. ... Ab urbe condita (related with Anno urbis conditae: AUC or a. ... AD redirects here. ... BCE redirects here. ... Anno Mundi (AM, in the year of the world) refers to a Calendar era counting from the creation of the world. ... The Spanish era or Era of the Caesars refers to the dating system used in Hispania until the fourteenth century and the adoption of Anno Domini. ... Before Present (BP) years are the units of time (counted backwards to the past) used to report raw radiocarbon ages and dates referenced to the BP scale origin in the year AD 1950 (identical to 1950 CE). ... The Islamic calendar or Muslim calendar (Arabic: التقويم الهجري; at-taqwÄ«m al-hijrÄ«; Persian: تقویم هجري قمری ‎ taqwÄ«m-e hejri-ye qamari; also called the Hijri calendar) is the calendar used to date events in many predominantly Muslim countries, and used by Muslims everywhere to determine the proper day on which to celebrate... The Sothic cycle or Canicular period is a period of 1461 ancient Egyptian years (of 365 days) or 1460 Julian years (averaging 365. ... // The astronomical time cycles mentioned in ancient Hindu astronomical and Puranic texts are remarkably similar to each other. ... Yuga (Devnāgari: युग) in Hindu philosophy refers to an epoch or era within a cycle of four ages: the Satya Yuga (or Krita Yuga), the Treta Yuga, the Dvapara Yuga and finally the Kali Yuga. ... Regnal year: Canon of Kings · King lists · Limmu · Seleucid era · Era name: Chinese · Japanese · Korean Calendars Pre-Julian Roman · Original Julian · Proleptic Julian · Revised Julian Gregorian · Proleptic Gregorian · Old Style and New Style Regnal year: the year of the reign of a sovereign. ... The Canon of Kings was a dated list of kings used by ancient astronomers as a convenient means to date astronomical phenomena, such as eclipses. ... Limmu was an Assyrian eponym. ... Coin of Philip V of Macedon (ruled 221–179 BC). ... An era name was assigned as the name of each year by the leader (emperor or king) of the East Asian countries of China, Korea, Japan, and Vietnam during some portion of their history. ... For other uses, see Calendar (disambiguation) A page from the Hindu calendar 1871–1872. ... The Roman calendar changed its form several times in the time between the foundation of Rome and the fall of the Roman Empire. ... The Julian calendar was a reform of the Roman calendar which was introduced by Julius Caesar in 46 BC and came into force in 45 BC (709 ab urbe condita). ... The proleptic Julian calendar is produced by extending the Julian calendar to dates preceding its official introduction in 45 BC. Historians since Bede have traditionally represented the years preceding AD 1 as 1 BC, 2 BC, etc. ... The Revised Julian calendar is a calendar that was considered for adoption by the Eastern Orthodox churches at a synod in Istanbul in May 1923. ... For the calendar of religious holidays and periods, see liturgical year. ... The proleptic Gregorian calendar is produced by extending the Gregorian Calendar to dates preceding its official introduction in 1582. ... Old Style redirects here. ... Lunisolar · Solar · Lunar · Islamic · Chinese sexagenary cycle A lunisolar calendar is a calendar whose date indicates both the moon phase and the time of the solar year. ... A solar calendar is a calendar whose dates indicate the position of the earth on its revolution around the sun (or equivalently the apparent position of the sun moving on the celestial sphere). ... A lunar calendar is a calendar that is based on cycles of the moon phase. ... The Islamic calendar or Muslim calendar (Arabic: التقويم الهجري; at-taqwÄ«m al-hijrÄ«; Persian: تقویم هجري قمری ‎ taqwÄ«m-e hejri-ye qamari; also called the Hijri calendar) is the calendar used to date events in many predominantly Muslim countries, and used by Muslims everywhere to determine the proper day on which to celebrate... The Chinese sexagenary cycle (Chinese: ; pinyin: ) is a cyclic numeral system of 60 combinations of the two basic cycles, the ten Heavenly Stems (天干; tiāngān) and the twelve Earthly Branches (地支; dìzhÄ«). These have been traditionally used as a means of numbering days and years, not only in China... Astronomical year numbering · ISO week date Astronomic time and techniques Astronomical chronology · Cosmic Calendar · Ephemeris · Galactic year · Metonic cycle · Milankovitch cycles Geologic time and techniques Deep time · Geological history · Eon · Eras · Periods · Faunal stage Chronostratigraphy · Geochronology · Isotope geochemistry · Law of superposition · Optical dating · Samarium-neodymium dating Archaeological techniques Dating methodology Absolute dating · Incremental dating · Archaeomagnetic dating · Dendrochronology · Glottochronology · Ice core · Lichenometry · Paleomagnetism · Radiocarbon dating · Radiometric dating · Tephrochronology · Thermoluminescence dating · Uranium-lead dating Relative dating · Seriation · Stratification Astronomical year numbering is based on BCE/CE (or BC/AD) year numbering, but follows normal decimal integer numbering more strictly. ... The ISO week date system is a leap week calendar system that is part of the ISO 8601 date and time standard. ... An ephemeris (plural: ephemerides) (from the Greek word ephemeros = daily) is a device giving the positions of astronomical objects in the sky. ... // Galactic time NGC 4414, a typical spiral galaxy alike our Milky Way Galactic time, not to confuse with siderial time, is the time that is described by our spin relative to the center of the galaxy. ... The Metonic cycle or Enneadecaeteris in astronomy and calendar studies is a particular approximate common multiple of the year (specifically, the seasonal tropical year) and the synodic month. ... Milankovitch cycles are the collective effect of changes in the Earths movements upon its climate, named after Serbian civil engineer and mathematician Milutin Milanković. The eccentricity, axial tilt, and precession of the Earths orbit vary in several patterns, resulting in 100,000 year ice age cycles of the... Deep time is the theory that Earth is billions of years old and thus had a long history of development and change. ... Geological time scale. ... In general usage, an eon (sometimes spelled æon) is an arbitrarily designated period of time. ... A geologic era is a subdivision of geologic time that is a separate classification that divides the Phanerozoic Eon into three parts timeframes. ... A geologic period is a subdivision of geologic time that divides an era into smaller timeframes. ... Faunal stages are a subdivision of geologic time used primarily by paleontologists who study fossils rather than by geologists who study rock formations. ... Chronostratigraphy is the branch of stratigraphy that studies the age of rock strata in relation to time. ... Geochronology is the science of determining the age of rocks, fossils, and sediments. ... Isotope geochemistry is an aspect of Geology based upon study of the relative and absolute concentrations of the elements and their isotopes in the Earth. ... See here for the superposition principle of physics. ... Optical dating is a method of determining how long ago minerals were last exposed to daylight. ... This article needs to be cleaned up to conform to a higher standard of quality. ... Dating material drawn from the archaeological record can made by a direct study of a artifact or may be deduced by association with materials found in the context the item is drawn from or inferred by its point of discovery in the sequence relative to datable contexts. ... Absolute dating is the process of determining a specific archaeological date. ... Incremental dating techniques allow the construction of year-by-year annual chronologies, which can be fixed ( linked to the present day and thus calendar or sidereal time) or floating. ... Archaeomagnetism (adjective archaeomagnetic) is the science of how to interpret signatures of the Earths magnetic field at past times that are recorded in archaeological materials. ... The growth rings of an unknown tree species, at Bristol Zoo, England Pinus taeda Cross section showing annual rings, Cheraw, South Carolina Pine stump showing growth rings Dendrochronology or tree-ring dating is the method of scientific dating based on the analysis of tree-ring growth patterns. ... Glottochronology refers to methods in historical linguistics used to estimate the time at which languages diverged, based on the assumption that the basic (core) vocabulary of a language changes at a constant average rate. ... Ice Core sample taken from drill. ... Lichens are a symbiotic relationship between algal and fungal communities and they increase in size radially as they grow. ... Paleomagnetism refers to the study of the record of the Earths magnetic field preserved in various magnetic minerals through time. ... Radiocarbon dating is a radiometric dating method that uses the naturally occurring isotope carbon-14 (14C) to determine the age of carbonaceous materials up to about 60,000 years. ... Radiometric dating (often called radioactive dating) is a technique used to date materials, based on a comparison between the observed abundance of particular naturally occurring radioactive isotopes and their known decay rates. ... Tephrochronology is a geochronolgical technique that utilises discreet layers of tephra—volcanic ash from a single eruption— to create a chronological framework in which palaeoenvironmental or archaeological records can be placed. ... Thermoluminescence (TL) dating is the determination by means of measuring the accumulated radiation dose of the time elapsed since material containing crystalline minerals was either heated (lava, ceramics) or exposed to sunlight (sediments). ... Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances. ... Before the advent of absolute dating in the 20th century, archaeologists and geologists were largely limited to the use of Relative Dating techniques. ... In archaeology, seriation is a method in relative dating in which artifacts of numerous sites, in the same culture, are placed in chronological order. ... In archaeology, especially in the course of excavation, stratification is of major interest and significance. ... Genetic techniques Amino acid dating · Molecular clock Related topics Chronicle · New Chronology · Periodization · Synchronoptic view · Timeline · Year zero ♦ Circa · Floruit

Amino acid dating is a technique used to estimate age in a wide variety of situations. ... The molecular clock (based on the molecular clock hypothesis (MCH)) is a technique in genetics, which researchers use to date when two species diverged. ... Generally a chronicle (Latin chronica, from Greek Χρόνος) is historical account of facts and events in chronological order. ... The New Chronology of Anatoly Timofeevich Fomenko is an attempt to rewrite world chronology, based on his conclusion that world chronology as we know it today is fundamentally flawed. ... Periodization is the attempt to categorize or divide time into discrete named blocks. ... A Synchronoptic view is a graphic display of a number of entities as they proceed through time. ... For other uses, see Timeline (disambiguation). ... For the political notion, see Year Zero (political notion). ... Look up Circa on Wiktionary, the free dictionary The Latin word circa, literally meaning about, is often used to describe various dates (often birth and death dates) that are uncertain. ... Floruit (or fl. ...