Eoraptor was one of the world's earliest dinosaurs. It was a two-legged meat-eater that lived between 230 and 225 million years ago, in what is now the northwestern region of Argentina. The type species is Eoraptor lunensis, which means 'dawn plunderer [from the Valley] of the Moon', denoting where it was originally discovered (Greek eos/ηως meaning 'dawn' or 'morning' and Latin lunensis meaning 'of the moon'). Paleontologists believe the Eoraptor resembles the common ancestor of all dinosaurs. It is known from several well-preserved skeletons. The Triassic is a geologic period that extends from about 251 ± 0. ... Image File history File links Download high-resolution version (1000x600, 263 KB) fifth version of eoraptor by me user debivort 12. ... The conservation status of a species is an indicator of the likelihood of that species continuing to survive either in the present day or the future. ... FOSSIL is a standard for allowing serial communication for telecommunications programs under DOS. FOSSIL is an acronym for Fido Opus Seadog Standard Interface Layer. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... For other uses, see Animal (disambiguation). ... Typical Classes See below Chordates (phylum Chordata) are a group of animals that includes the vertebrates, together with several closely related invertebrates. ... Subclasses Anapsida Diapsida Synonyms Reptilia Laurenti, 1768 Reptiles are tetrapods and amniotes, animals whose embryos are surrounded by an amniotic membrane, and members of the class Sauropsida. ... Orders Saurischia    Sauropodomorpha    Theropoda Ornithischia Dinosaurs are giant reptiles that dominated the terrestrial ecosystem for most of their 165-million year existence. ... Groups Sauropodomorpha    Saturnalia    Prosauropoda    Sauropoda Theropoda    Eoraptor    Herrerasauridae    Ceratosauria    Tetanurae       Aves(extant) Saurischians (from the Greek Saurischia meaning lizard hip) are one of the two orders/branches of dinosaurs. ... Subdivisions ?Eoraptor Herrerasauria Coelophysoidea Ceratosauria Cryolophosaurus Spinosauridae Carnosauria Coelurosauria Theropods (beast foot) are a group of bipedal saurischian dinosaurs. ... This article does not cite any references or sources. ... Paul Callistus Sereno (born October 11, 1957) is an American paleontologist who is the discoverer of several new dinosaur species on several continents. ... Year 1993 (MCMXCIII) was a common year starting on Friday (link will display full 1993 Gregorian calendar). ... 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. ... This article or section does not cite its references or sources. ... This tigers sharp teeth and strong jaws are the classical physical traits expected from carnivorous mammalian predators A carnivore (IPA: ), meaning meat eater (Latin carne meaning flesh and vorare meaning to devour), is an animal that eats a diet consisting mainly of meat, whether it comes from live animals... Mega-annum, usually abbreviated as Ma, is a unit of time equal to one million years. ... Type specimens When a new species is discovered, more important than creating a new and unique name for the species is developing a reasonably detailed description. ... Latin is an ancient Indo-European language originally spoken in Latium, the region immediately surrounding Rome. ... A paleontologist carefully chips rock from a column of dinosaur vertebrae. ... 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. ...

Eoraptor compared in size to a human.

Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ...

Description and behavior

It had a thin body that grew to about 1 meter (3 feet) in length, with an estimated weight of about 10 kilograms (22 pounds). It ran digitigrade, upright on its hind legs. Its fore limbs were only half the length of its hind limbs and it had five digits on each 'hand'. Three of those digits, the longest of the five, ended in large claws and were presumably used to handle prey. Scientists have surmised that the fourth and fifth digits were too tiny to be of any use in hunting. The metre, or meter (symbol: m) is the SI base unit of length. ... A foot (plural: feet or foot;[1] symbol or abbreviation: ft or, sometimes, ′ – a prime) is a unit of length, in a number of different systems, including English units, Imperial units, and United States customary units. ... The U.S. National Prototype Kilogram, which currently serves as the primary standard for measuring mass in the U.S. It was assigned to the United States in 1889 and is periodically recertified and traceable to the primary international standard, The Kilogram, held at the Bureau International des Poids et... The pound (abbreviations: lb or, sometimes in the United States, #) is a unit of mass (called weight in everyday parlance) in a number of different systems, including English units, Imperial units, and United States customary units. ... A digitigrade is an animal that stands or walks on its digits, or toes. ... Cat claw A claw is a curved pointed appendage, found at the end of a toe or finger or, in arthropods, of the tarsus. ... Prey can refer to: Look up Prey in Wiktionary, the free dictionary A prey animal eaten by a predator in an act called predation. ...

Eoraptor probably ate mostly small animals. It was a swift sprinter and, upon catching its prey, it would use claws and teeth to tear the prey apart. However, it had both carnivore-type and herbivore-type teeth, so it could possibly have been omnivorous. For other uses, see Animal (disambiguation). ... This tigers sharp teeth and strong jaws are the classical physical traits expected from carnivorous mammalian predators A carnivore (IPA: ), meaning meat eater (Latin carne meaning flesh and vorare meaning to devour), is an animal that eats a diet consisting mainly of meat, whether it comes from live animals... A deer and two fawns feeding on some foliage A herbivore is often defined as any organism that eats only plants[1]. By that definition, many fungi, some bacteria, many animals, about 1% of flowering plants and some protists can be considered herbivores. ... This article or section does not adequately cite its references or sources. ...

Early dinosaur

The bones of this primitive dinosaur were first discovered in 1991, by University of Chicago paleontologist Paul Sereno, in the Ischigualasto Basin of Argentina. During the Late Triassic Period, this was a river valley but is now desert badlands. Eoraptor was found in the Ischigualasto Formation, the same formation that yielded Herrerasaurus, a very early theropod. By 1993 it had been determined to be one of the earliest dinosaurs. Its age was determined by several factors, not least because it lacked the specialised features of any of the major groups of later dinosaurs, including its lack of specialized predatory features. Unlike later carnivores, it lacked a sliding joint at the articulation of the lower jaw, with which to hold large prey. Furthermore, only some of its teeth were curved and saw-edged, unlike those in a later predator's mouth. Year 1991 (MCMXCI) was a common year starting on Tuesday (link will display the 1991 Gregorian calendar). ... The University of Chicago is a private university located principally in the Hyde Park neighborhood of Chicago. ... Paul Callistus Sereno (born October 11, 1957) is an American paleontologist who is the discoverer of several new dinosaur species on several continents. ... The Triassic is a geologic period that extends from about 251 ± 0. ... A geologic period is a subdivision of geologic time that divides an era into smaller timeframes. ... This article is about arid terrain. ... The Chinle Badlands at Grand Staircase-Escalante National Monument. ... Species (type) Reig, 1963 Synonyms Ischisaurus Reig, 1963 Frenguellisaurus Novas, 1986 Herrerasaurus (meaning Herreras lizard, after the name of the rancher who discovered the first fossil of the animal) was one of the earliest carnivorous dinosaurs. ... Year 1993 (MCMXCIII) was a common year starting on Friday (link will display full 1993 Gregorian calendar). ... Orders Saurischia    Sauropodomorpha    Theropoda Ornithischia Dinosaurs are giant reptiles that dominated the terrestrial ecosystem for most of their 165-million year existence. ... This snapping turtle is trying to make a meal of a Canada goose, but the goose is too wary. ... Human jaw front view Human jaw left view Human jaw top view The jaw is either of the two opposable structures forming, or near the entrance to, the mouth. ... Types of teeth Molars are used for grinding up foods Carnassials are used for slicing food. ...

Eoraptor belonged to a major group of dinosaurs called saurischians, or lizard-hipped dinosaurs. Their hip structures are similar to that of the modern lizard. Groups Sauropodomorpha    Saturnalia    Prosauropoda    Sauropoda Theropoda    Eoraptor    Herrerasauridae    Ceratosauria    Tetanurae       Aves(extant) Saurischians (from the Greek Saurischia meaning lizard hip) are one of the two orders/branches of dinosaurs. ...

The fact that it possessed some herbivore teeth and five fully developed 'fingers' has led scientists to place Eoraptor at more ancient than even Herrerasaurus. Only some prosauropods, recently discovered in Madagascar, are thought to be older. A deer and two fawns feeding on some foliage A herbivore is often defined as any organism that eats only plants[1]. By that definition, many fungi, some bacteria, many animals, about 1% of flowering plants and some protists can be considered herbivores. ... Families Plateosauridae (paraphyletic) Plesion Riojasaurus Massospondylidae Yunnanosauridae Prosauropoda or prosauropods were a group of early herbivorous dinosaurs that lived during the Late Triassic and early Jurassic periods. ...

External links

Wikispecies has information related to:

Eoraptor

• Paul Sereno's Paleontology website
• Paleobiology Database entry

Dinosaurs Portal