This article considers the history of zoology before the theory of evolution proposed by Charles Darwin in 1859. Zoology (Greek zoon = animal and logos = word) is the biological discipline which involves the study of animals. ... Charles Darwin gave new stimulus and new direction to morphology and physiology, by uniting them as part of a common biological theory: the theory of organic evolution but a part of the wider doctrine of universal evolution based on the laws of physics and chemistry. ... Zoology (Greek zoon = animal and logos = word) is the biological discipline which involves the study of animals. ... Jump to: navigation, search Charles Darwin, father of the theory of evolution by natural selection. ... Jump to: navigation, search In his lifetime Charles Darwin gained international fame as a controversial and influential scientist. ... 1859 is a common year starting on Saturday. ...

Pre-scientific zoology

Humans have been fascinated by the other members of the animal kingdom throughout history. In early Europe, they gathered up and treasured stories of strange animals from distant lands or deep seas, such as are recorded in the Physiologus, in the works of Albertus Magnus (On Animals), and others. These accounts were often apocryphal and creatures were often described as "legendary." This period was succeeded by the age of collectors and travellers, when many of the stories were actually demonstrated as true when the living or preserved specimens were brought to Europe. World map showing Europe (geographically) When considered a continent, Europe is the worlds second-smallest continent in terms of area, with an area of 10,600,000 km² (4,140,625 square miles), making it larger than Australia only. ... The Physiologus was a predecessor of bestiaries (books of beasts). ... Jump to: navigation, search Albertus Magnus (fresco, 1352, Treviso, Italy) Albertus Magnus (1193? – November 15, 1280), also known as Saint Albert the Great and Albert of Cologne, was a Dominican friar who became famous for his universal knowledge and advocacy for the peaceful coexistence of science and religion. ... In Judeo-Christian theologies, apocrypha refers to religious Sacred text that have questionable authenticity or are otherwise disputed. ...

The rise of the naturalist

Verification by collecting of things, instead of the accumulation of anecdotes, then became more common, and scholars developed a new faculty of careful observation. The early collectors of natural curiosities were the founders of zoology, and to this day the naturalists and, museum curators and systematists, play an important part in the progress of zoology. Indeed, the historical importance of this aspect or branch of zoology was previously so great that the name zoology had until the beginning of the 20th century been associated entirely with it, to the exclusion of the study of minute anatomical structure (anatomy) and function (physiology). Anatomy and the study of animal mechanism, animal physics and animal chemistry, all of which form part of a true zoology, were initially excluded from the usual definition of the word by the fact that the zoologist had museums unlike botanists who possessed living specimens. Early zoologists were deprived of the means of anatomical and physiological study and only later supplied by the method of preserving animal bodies in alcohol when the demands of medicine for a knowledge of the structure of the human animal brought into existence a separate and special study of human anatomy and physiology. Zoology (Greek zoon = animal and logos = word) is the biological discipline which involves the study of animals. ... Natural history is an umbrella term for what are now usually viewed as a number of distinct scientific disciplines. ... A curator of a cultural heritage institution (e. ... Systematics is the term used by John G Bennett for the study of multi-term systems. ... (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999 in the... Anatomical drawing of the human muscles from the Encyclopédie. ... Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... Jump to: navigation, search In general usage, alcohol (from Arabic al-ghawl الغول) refers almost always to ethanol, also known as grain alcohol, and often to any beverage that contains ethanol (see alcoholic beverage). ... Jump to: navigation, search Medicine is a branch of health science concerned with maintaining human health and restoring it by treating disease and injury; it is both an area of knowledge, a science of body organ system|systems and diseases and their treatment, and the applied practice of that knowledge. ... Jump to: navigation, search Human anatomy or anthropotomy is a special field within anatomy. ... Human physiology is the science of the mechanical, physical, and biochemical functions of normal humans or human tissues or organs. ...

From the study of human structure the knowledge of the anatomy of animals proceeded. Scientists who studied the structure of the human body were able to compare human anatomical structures with those of other animals. Comparative anatomy came into existence as a branch of inquiry apart from zoology, and it was only in the latter part of the 19th century that the limitation of the word zoology to a knowledge of animals which expressly excludes the consideration of their internal structure was rejected by scientists. It is now generally recognised that zoology and comparative anatomy are essentially synonymous, and museum naturalists study both the anatomy (inside) and the morphology (outside) of animals. Comparative anatomy is the study of similarities and differences in organisms. ... Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ...

16th century developments

Scientific zoology really started in the 16th century with the awakening of the new spirit of observation and exploration, but for a long time ran a separate course uninfluenced by the progress of the medical studies of anatomy and physiology. The active search for knowledge by means of observation and experiment found its natural home in the universities. Owing to the connection of medicine with these seats of learning, it was natural that the study of the structure and functions of the human body and of the animals nearest to man should take root there; the spirit of inquiry which now for the first time became general showed itself in the anatomical schools of the Italian universities of the 16th century, and spread fifty years later to Oxford. (15th century - 16th century - 17th century - more centuries) As a means of recording the passage of time, the 16th century was that century which lasted from 1501 to 1600. ... Jump to: navigation, search Medicine is a branch of health science concerned with maintaining human health and restoring it by treating disease and injury; it is both an area of knowledge, a science of body organ system|systems and diseases and their treatment, and the applied practice of that knowledge. ... Jump to: navigation, search A professor giving a lecture at the Helsinki University of Technology A university is an institution of higher education and of research, which grants academic degrees. ... Jump to: navigation, search The University of Oxford, located in the city of Oxford, England, is the oldest university in the English-speaking world. ...

17th century developments

In the 17th century, the lovers of the new philosophy, the investigators of nature by means of observation and experiment, banded themselves into academies or societies for mutual support and intercourse. The first founded of surviving European academies, the Academia Naturae Curiosorum (1651) especially confined itself to the description and illustration of the structure of plants and animals; eleven years later (1662) the Royal Society of London was incorporated by royal charter, having existed without a name or fixed organisation for seventeen years previously (from 1645). (16th century - 17th century - 18th century - more centuries) As a means of recording the passage of time, the 17th century was that century which lasted from 1601-1700. ... The German Academy of Natural Scientists Leopoldinais the oldest Germany. ... // Events January 1 - Charles II crowned King of Scotland in Scone. ... Events March 18 – Short-timed experiment of the first public buses holding 8 passengers begins in Paris May 3/May 2 - Catherine of Braganza marries Charles II of England – as part of the dowry, Portugal cedes Bombay and Tangier to England May 9 - Samuel Pepys witnessed a Punch and Judy... The Royal Society of London is claimed to be the oldest learned society still in existence and was founded in 1660. ... In the United Kingdom and Canada a Royal Charter is a charter granted by the Sovereign on the advice of the Privy Council, which creates or gives special status to an incorporated body. ... // Events January 10 - Archbishop Laud executed on Tower Hill, London. ...

A little later the Academy of Sciences of Paris was established by Louis XIV. The influence of these great academies of the 17th century on the progress of zoology was precisely to effect that bringing together of the museum-men and the physicians or anatomists which was needed for further development. Whilst the race of collectors and systematisers culminated in the latter part of the 18th century in Linnaeus, a new type of student made its appearance in such men as John Hunter and other anatomists, who, not satisfied with the superficial observations of the popular zoologists, set themselves to work to examine anatomically the whole animal kingdom, and to classify its members by aid of the results of such profound study. Academy of Sciences can refer to a national academy or another learned society dedicated to sciences. ... Jump to: navigation, search The Eiffel Tower has become a symbol of Paris throughout the world. ... Louis XIV King of France and Navarre By Hyacinthe Rigaud (1701) Louis XIV (Louis-Dieudonné) (September 5, 1638–September 1, 1715) reigned as King of France and King of Navarre from May 14, 1643 until his death. ... (16th century - 17th century - 18th century - more centuries) As a means of recording the passage of time, the 17th century was that century which lasted from 1601-1700. ... Physician examining a child The word physician should not be confused with physicist, which means a scientist in the area of physics. ... Greek anatome, from ana-temnein, to cut up), is the branch of biology that deals with the structure and organization of living things; thus there is animal anatomy (zootomy) and plant anatomy (phytonomy). ... (17th century - 18th century - 19th century - more centuries) As a means of recording the passage of time, the 18th century refers to the century that lasted from 1701 through 1800. ... Jump to: navigation, search Carolus Linnaeus Carl Linnaeus, also known after his ennoblement as Carl von Linné â–¶(?), and in English usually under the Latinized name Carolus Linnaeus (May 23, 1707 – January 10, 1778), was a Swedish botanist who laid the foundations for the modern scheme of taxonomy. ... Engraving of John Hunter (1728 – 1793) taken from the original portrait by Sir Joshua Reynolds, which is in the Royal College of Surgeons. ...

Under the influence of the touchstone of strict inquiry set on foot by the Royal Society, the marvels of witchcraft, sympathetic powders, and other relics of mediaeval superstition disappeared, whilst accurate observations and demonstrations of a host of new wonders accumulated, amongst which were numerous contributions to the anatomy of animals, and none perhaps more noteworthy than the observations, made by the aid of microscopes constructed by himself, of Leeuwenhoek, the Dutch naturalist (1683), some of whose instruments were presented by him to the Society. The Royal Society of London for the Improvement of Natural Knowledge, known simply as the Royal Society, is claimed to be the oldest learned society still in existence. ... Jump to: navigation, search The term witchcraft (and witch) is a controversial one with a complicated history. ... Jump to: navigation, search 1852 microscope Compound microscope made by John Cuff in 1750 A microscope (Greek: micron = small and scopos = aim) is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. ... Jump to: navigation, search Anton van Leeuwenhoek Anton van Leeuwenhoek (October 24, 1632 - August 30, 1723, full name Thonius Philips van Leeuwenhoek) was a tradesman and scientist from Delft, Netherlands. ... Events June 6 - The Ashmolean Museum opens as the worlds first university museum. ...

19th century developments

Development of the microscope

It was not until the 19th century that the microscope, thus early applied by Leeuwenhoek, Malpighi, Hooke, and Swammerdam to the study of animal structure, was perfected as an instrument, and accomplished for zoology its final and most important service. The perfecting of the microscope led to a full comprehension of the great doctrine of cell structure and the establishment of the facts - (1) that all organisms are either single corpuscles (so-called "cells") of living material (microscopic animalcules, etc.) or are built up of an immense number of such units; (2) that all organisms begin their individual existence as a single unit or corpuscle of living substance, which multiplies by binary fission, the products growing in size and multiplying similarly by binary fission; and (3) that the life of a multicellular organism is the sum of the activities of the corpuscular units of which it consists, and that the processes of life must be studied in and their explanation obtained from an understanding of the chemical and physical changes which go on in each individual corpuscle or unit of living material or protoplasm. Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... Marcello Malpighi (March 10, 1628 - November 29, 1694) was an Italian doctor, who gave his name to several physiological features. ... Jump to: navigation, search Robert Hooke, FRS (July 18, 1635 - March 3, 1703), one of the greatest experimental scientists of the seventeenth century, played an important role in the scientific revolution. ... Jan Swammerdam (February 12, 1637 - February 17, 1680) was a Dutch scientist. ... Jump to: navigation, search Cells in culture, stained for keratin (red) and DNA (green) The cell is the structural and functional unit of all living organisms, and are sometimes called the building blocks of life. ... Protoplasm is the living substance inside the cell. ...

Developments in other sciences impacting zoology

Meanwhile the astronomical theories of development of the solar system from a gaseous condition to its present form, put forward by Kant and by Laplace, had impressed men's minds with the conception of a general movement of spontaneous progress or development in all nature. The science of geology came into existence, and the whole panorama of successive stages of the Earths history, each with its distinct population of strange animals and plants, unlike those of the present day and simpler in proportion as they recede into the past, was revealed by Georges Cuvier, Agassiz, and others. The history of the crust of the earth was explained by Lyell as due to a process of slow development, in order to effect which he called in no cataclysmic agencies, no mysterious forces differing from those operating at the present day. Thus he carried on the narrative of orderly development from the point at which it was left by Kant and Laplace - explaining by reference to the ascertained laws of physics and chemistry the configuration of the Earth, its mountains and seas, its igneous and its stratified rocks, just as the astronomers had explained by those same laws the evolution of the Sun and planets from diffused gaseous matter of high temperature. The suggestion that living things must also be included in this great development was obvious. Astrometry: the study of the position of objects in the sky and their changes of position. ... Jump to: navigation, search Presentation of the solar system (not to scale) The solar system is the retinue of objects gravitationally bound to our Sun. ... A gas is one of the phases of matter. ... Jump to: navigation, search Immanuel Kant (April 22, 1724 – February 12, 1804) was a German philosopher and scientist (astrophysics, mathematics, geography, anthropology) from East Prussia, generally regarded as one of Western societys and modern Europes most influential thinkers and the last major philosopher of the Enlightenment. ... Jump to: navigation, search Pierre-Simon Laplace Pierre-Simon, Marquis de Laplace (March 23, 1749 – March 5, 1827) was a French mathematician and astronomer who put the final capstone on mathematical astronomy by summarizing and extending the work of his predecessors in his five volume Mécanique Céleste (Celestial... Jump to: navigation, search Geology (from Greek γη- (ge-, the earth) and λογος (logos, word, reason)) is the science and study of the Earth, its composition, structure, physical properties, history, and the processes that shape it. ... Jump to: navigation, search Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third-closest planet to the Sun. ... Jump to: navigation, search Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Subregnum Bilateria  Acoelomorpha  Orthonectida  Rhombozoa  Myxozoa  Superphylum Deuterostomia     Chordata (vertebrates, etc. ... Jump to: navigation, search Divisions Land plants (embryophytes) Non-vascular plants (bryophytes) Hepaticophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants... Georges Cuvier Baron Georges Léopold Chrétien Frédéric Dagobert Cuvier (August 23, 1769 - May 13, 1832) was a French naturalist and zoologist. ... Jean Louis Rodolphe Agassiz (May 28, 1807-December 14, 1873) was a Swiss-born American zoologist, glaciologist, and geologist, the husband of educator Elizabeth Cabot Cary Agassiz, and one of the first world-class American scientists. ... In geology, a crust is the outer layer of a planet, part of its lithosphere. ... Charles Lyell Sir Charles Lyell (November 14, 1797 – February 22, 1875), British lawyer, geologist, and popularizer of uniformitarianism. ... Since antiquity, people have tried to understand the behavior of matter: why unsupported objects drop to the ground, why different materials have different properties, and so forth. ... // Introduction Chemistry is a large field encompassing many subdisciplines that often overlap with significant portions of other sciences. ... Mount McKinley in Alaska has one of the largest visible base-to-summit elevation differences anywhere A mountain is a landform that extends above the surrounding terrain in a limited area. ... Sunset at sea Look up Sea on Wiktionary, the free dictionary Look up maritime in Wiktionary, the free dictionary. ... Jump to: navigation, search Volcanic rock on North America Plutonic rock on North America Igneous rocks are formed when molten rock (magma) cools and solidifies, with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. ... An astronomer or astrophysicist is a scientist whose area of research is astronomy or astrophysics. ... Jump to: navigation, search The Sun is the star at the centre of our Solar system. ... Jump to: navigation, search A planet in common parlance is a large object in orbit around a star that is not a star itself. ... A gas is one of the phases of matter. ...

The delay in the establishment of the doctrine of organic evolution was due, not to the ignorant and unobservant, but to the leaders of zoological and botanical science. Knowing the almost endless complexity of organic structures, realising that man himself with all the mystery of his life and consciousness must be included in any explanation of the origin of living things, they preferred to regard living things as something apart from the rest of nature, specially cared for, specially created by a Divine Being. Thus it was that the so-called Natur-philosophen of the last decade of the 18th century, and their successors in the first quarter of the 19th, found few adherents among the working zoologists and botanists. Jean-Baptiste Lamarck, Treviranus, Erasmus Darwin, Goethe, and Saint-Hilaire preached to deaf ears, for they advanced the theory that living beings had developed by a slow process of transmutation in successive generations from simpler ancestors, and in the beginning from simplest formless matter, without being able to demonstrate any existing mechanical causes by which such development must necessarily be brought about. They were met by the criticism that possibly such a development had taken place; but, as no one could show as a simple fact of observation that it had taken place, nor as a result of legitimate inference that it must have taken place, it was quite as likely that the past and present species of animals and plants had been separately created or individually brought into existence by unknown and inscrutable causes, and (it was held) the truly scientific man would refuse to occupy himself with such fancies, whilst ever centinuing to concern himself with the observation and record of indisputable facts. The critics did well; for the Natur-philosophen, though right in their main conception, were premature. Jump to: navigation, search The term God is capitalized in the English language as a proper noun when used to refer to a specific monotheistic concept of a supernatural Supreme Being in accordance with Christian, Jewish (sometimes as G-d - cf. ... (17th century - 18th century - 19th century - more centuries) As a means of recording the passage of time, the 18th century refers to the century that lasted from 1701 through 1800. ... Jean-Baptiste Lamarck Jean-Baptiste Pierre Antoine de Monet, Chevalier de Lamarck (August 1, 1744 – December 28, 1829) was a major 19th century French naturalist, who was one of the first to use the term biology in its modern sense. ... Erasmus Darwin Stone-cast bust of Erasmus Darwin, by William John Coffee, c 1795, (Crown Derby Modeller and world renown artist) Erasmus Darwin (December 12, 1731 – April 18, 1802) trained as a physician and wrote extensively on medicine and botany, as well as poetry. ... Jump to: navigation, search Johann Wolfgang von Goethe Johann Wolfgang von Goethe â–¶(?) (IPA: ) (28 August 1749 – 22 March 1832) was a German novelist, dramatist, poet, humanist, scientist, philosopher, and for ten years chief minister of state at Weimar. ... Several notable persons have been named Saint-Hilaire: Etienne Geoffroy Saint-Hilaire (1772-1844), French zoologist Isidore Geoffroy Saint-Hilaire (1805-1861), his son, also a zoologist Jules Barthélemy-Saint-Hilaire (1805-1895), French philosopher, journalist and statesman Saint-Hilaire is also the name or part of the name of...

Zoology since 1859: Darwin and theory of evolution

Then, in 1859, Charles Darwin placed the whole theory of organic evolution on a new footing, by his discovery of a process by which organic evolution can occur, and provided observational evidence that it had done so. This changed the attitudes of most exponents of the scientific method. Darwin's discoveries revolutionised the zoological and botanical sciences, by introducing the theory of evolution by natural selection as an explanation for the diversity of all animal and plant life. The subject-matter of this new science, or branch of biological science, had been neglected: it did not form part of the studies of the collector and systematist, nor was it a branch of anatomy, nor of the physiology pursued by medical men, nor again was it included in the field of microscopy and the cell theory. 1859 is a common year starting on Saturday. ... Jump to: navigation, search In his lifetime Charles Darwin gained international fame as a controversial and influential scientist. ... Theory has a number of distinct meanings in different fields of knowledge, depending on the context and their methodologies. ... Jump to: navigation, search Charles Darwin, father of the theory of evolution by natural selection. ... Jump to: navigation, search Natural selection is a process by which biological populations are altered over time, as a result of the propagation of heritable traits that affect the capacity of individual organisms to survive and reproduce. ...

The area of biological knowledge which Darwin was the first to subject to scientific method and to render, as it were, contributory to the great stream formed by the union of the various branches, is that which relates to the breeding of animals and plants, their congenital variations, and the transmission and perpetuation of those variations. This branch of biological science may be called thremmatology - the science of breeding. Outside the scientific world, an immense mass of observation and experiment had grown up in relation to this subject. From the earliest times the shepherd, the farmer, the horticulturist, and the fancier had for practical purposes made themselves acquainted with a number of biological laws, and successfully applied them without exciting more than an occasional notice from the academic students of biology. Darwin made use of these observations and formulated their results to a large extent as the laws of variation and heredity. As the breeder selects a congenital variation which suits his requirements, and by breeding from the animals (or plants) exhibiting that variation obtains a new breed specially characterised by that variation, so in nature is there a selection amongst all the congenital variations of each generation of a species. This selection depends on the fact that more young are born than the natural provision of food will support. In consequence of this excess of births there is a struggle for existence and a survival of the fittest, and consequently an ever-present necessarily acting selection, which either maintains accurately the form of the species from generation to generation or leads to its modification in correspondence with changes in the surrounding circumstances which have relation to its fitness for success in the struggle for life, structures to the service of the organisms in which they occur. Breeding has several meanings related to procreation: In animal husbandry and in horticulture the selection of stock for propagation and the act of insemination by natural or artificial means is called breeding. ... In a draw in a mountainous region, a shepherd guides a flock of about 20 sheep amidst scrub and olive trees. ... Farmer spreading grasshopper bait in his alfalfa field. ... The Latin words hortus (garden plant) and cultura (culture) together form horticulture, classically defined as the culture or growing of garden plants. ... In music, variation is a formal technique where material is altered during repetition; reiteration with changes. ... Jump to: navigation, search Heredity (the adjective is hereditary) is the transfer of characteristics from parent to offspring, either through their genes or through the social institution called inheritance (for example, a title of nobility is passed from individual to individual according to relevant customs and/or laws). ... Jump to: navigation, search Herbert Spencer coined the phrase survival of the fittest Survival of the fittest is a phrase which is a shorthand for a concept relating to competition for survival or predominance. ...

It cannot be said that previously to Darwin there had been any very profound study of teleology, but it had been the delight of a certain type of mind, that of the lovers of nature or naturalists par excellence as they were sometimes termed, to watch the habits of living animals and plants and to point out the remarkable ways in which the structure of each variety of organic life was adapted to the special circumstances of life of the variety or species. The astonishing colours and grotesque forms of some animals and plants which the museum zoologists gravely described without comment were shown by these observers of living nature to have their significance in the economy of the organism possessing them; and a general doctrine was recognized, to the effect that no part or structure of an organism is without definite use and adaptation, being designed by the Creator for the benefit of the creature to which it belongs, or else for the benefit, amusement or instruction of his highest creatureman. Teleology in this form of the doctrine of design was never very deeply rooted amongst scientific anatomists and systematists. It was considered permissible to speculate somewhat vaguely on the subject of the utility of this or that startling variety of structure; but few attempts, though some of great importance, were made systematically to explain by observation and experiment the adaptation of organic structures to particular purposes in the case of the lower animals and plants. Teleology had, indeed, an important part in the development of physiology - the knowledge of the mechanism, the physical and chemical properties, of the parts of the body of man and the higher animals allied to him. But, as applied to lower and more obscure forms of life, teleology presented almost insurmountable difficulties; and consequently, in place of exact experiment and demonstration, the most reckless though ingenious assumptions were made as to the utility of the parts and organs of lower animals.

Darwin's theory had as one of its results the reformation and rehabilitation of teleology. According to that theory, every organ, every part, colour and peculiarity of an organism, must either be of benefit to that organism itself or have been so to its ancestors: no peculiarity of structure or general conformation, no habit or instinct in any organism, can be supposed to exist for the benefit or amusement of another organism, not even for the delectation of man himself.

A very subtle and important qualification of this generalization has to be recognized (and was recognized by Darwin) in the fact that owing to the interdependence of the parts of the bodies of living things and their profound chemical interactions and peculiar structural balance (what is called organic polarity) the variation of one single part (a spot of colour, a tooth, a claw, a leaflet) may, and demonstrably does in many cases entail variation of other parts what are called correlated variations. Hence many structures which are obvious to the eye, and serve as distinguishing marks of separate species, are really not themselves of value or use, btit are the necessary concomitants of less obvious and even altogether obscure qualities, which are the real characters upon which selection is acting. Such correlated variations may attain to great size and complexity without being of use. But eventually they may in turn become, in changed conditions, of selective value. Thus in many cases the difficulty of supposing that selection has acted on minute and imperceptible initial variations, so small as to have no selective value, may be got iid of. A useless correlated variation may have attained great volume and quality before it is (as it were) seized upon and perfected by natural selection. All organisms are essentially and necessarily built up by such correlated variations.

Necessarily, according to the theory of natural selection, structures either are present because they are selected as useful or because they are still inherited from ancestors to whom they were useful, though no longer useful to the existing representatives of those ancestors. Structures previously inexplicable were now explained as survivals from a past age, no longer useful though once of value. Every variety of form and colour was urgently and absolutely called upon to produce its title to existence either as an active useful agent or as a survival. Darwin himself spent a large part of the later years of his life in thus extending the new teleology.

The old doctrine of types, which was used by the philosophically minded zoologists (and botanists) of the first half of the 19th century as a ready means of explaining the failures and difficulties of the doctrine of design, fell into its proper place under the new dispensation. The adherence to type, the favourite conception. of the transcendental morphologist, was seen to be nothing more than the expression of one of the laws of thremmatology, the persistence of hereditary transmission of ancestral characters, even when they have ceased to be significant or valuable in the struggle for existence, whilst the so-called evidences of design which was supposed to modify the limitations of types assigned to Himself by the Creator were seen to be adaptations due to the selection and intensification by selective breeding of fortuitous congenital variations, which happened to prove more useful than the many thousand other variations which did not survive in the struggle for existence.

Thus not only did Darwins theory give a new basis to the study of organic structure, but, whilst rendering the general theory of organic evolution equally acceptable and necessary, it explained the existence of low and simple forms of life as survivals of the earliest ancestry of the more highly complex forms, and revealed the classifications of the systematist as unconscious attempts to construct the genealogical tree or pedigree of plants and animals. Finally, it brought the simplest living matter or formless protoplasm before the mental vision as the starting point whence, by the operation of necessary mechanical causes, the highest forms have been evolved, and it rendered unavoidable the conclusion that this earliest living material was itself evolved by gradual processes, the result also of the known and recognized laws of physics and chemistry, from material which we should call not living. It abolished the conception of life as an entity above and beyond the common properties of matter, and led to the conviction that the marvellous and exceptional qualities of that which we call living matter are nothing more nor less than an exceptionally complicated development of those chemical and physical properties which we recognize in a gradually ascending scale of evolution in the carbon compounds, containing nitrogen as well as oxygen, sulphur and hydrogen as constituent atoms of their enormous molecules. Thus mysticism was finally banished from the domain of biology, and zoology became one of the physical sciencesthe science which seeks to arrange and discuss the phenomena of animal life and form, as the outcome of the operation of the laws of physics and chemistry.

A subdivision of zoology which was at one time in favour is simply into morphology and physiology, the study of form and structure on the one hand, and the study of the activities and functions of the forms and structures of the other. But a logical division like this is not necessarily conducive to the ascertainment and remembrance of the historical progress and present significance of the science. No such distinction of mental activities as that involved in the division of the study of animal life into morphology and physiology has ever really existed: the investigator of animal forms has never entirely ignored the functions of the forms studied by him, and the experimental inquirer into the functions and properties of animal tissues and organs has always taken very careful account of the forms of those tissues and organs. A more instructive subdivision must be one which corresponds to the separate currents of thought and mental preoccupation which have been historically manifested in western Europe in the gradual evolution of what is to-day the great river of zoological doctrine to which they have all been rendered contributory.

This article incorporates text from the 1911 Encyclopædia Britannica, which is in the public domain. Jump to: navigation, search Supporters contend that the Eleventh Edition of the Encyclopædia Britannica (1910-1911) represents the sum of human knowledge at the beginning of the 20th century; indeed, it was advertised as such. ... The public domain comprises the body of all creative works and other knowledge—writing, artwork, music, science, inventions, and others—in which no person or organization has any proprietary interest. ...