zoology, branch of biology concerned with the study of animal life. From earliest times animals have been vitally important to man; cave art demonstrates the practical and mystical significance animals held for prehistoric man. Early efforts to classify animals were based on physical resemblance, habitat, or economic use. Although Hippocrates and Aristotle did much toward organizing the scientific thought of their times, systematic investigation declined under the Romans and, after Galen's notable contributions, came to a virtual halt lasting through the Middle Ages (except among the Arab physicians). With the Renaissance direct observation of nature revived; landmarks were Vesalius' anatomy and Harvey's demonstration of the circulation of blood. The invention of the microscope and the use of experimental techniques expanded zoology as a field and established many of its branches, e.g., cytology and histology. Studies in embryology and morphology revealed much about the nature of growth and the biological relationships of animals. The system of binomial nomenclature (see classification) was devised to indicate these relationships; Linnaeus was the first to make it consistent and apply it systematically. Paleontology, the study of fossil organisms, was founded as a science by Cuvier c.1812. Knowledge of physiological processes expanded greatly when physiology was integrated with the chemical and other physical sciences. The establishment of the cell theory in 1839 and the acceptance of protoplasm as the stuff of life 30 years later gave impetus to the development of genetics. Lamarck, Mendel, and Darwin presented concepts that revolutionized scientific thought. Their theories of evolution and of the physical basis of heredity prompted research into all life processes and into the relationships of all organisms. The classic work of Pasteur and Koch opened up bacteriology as a field. Modern zoology has not only concentrated on the cell, its parts and functions, and on expanding the knowledge of cytology, physiology, and biochemistry, but it has also explored such areas as psychology, anthropology, and ecology.

Branch of biology concerned with members of the animal kingdom and with animal life in general. The science originated in the works of Hippocrates, Aristotle, and Pliny. The contributions of individuals such as William Harvey (the circulation of blood), Carolus Linnaeus (system of nomenclature), Georges-Louis de Buffon (natural history), Georges Cuvier (comparative anatomy), and Claude Bernard (homeostasis) greatly advanced the field. The 1859 publication of Charles Darwin's On the Origin of Species by Means of Natural Selection was a major turning point. Since that time, the study of genetics has become essential in zoological studies.

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Zoology (from Greek ζῷον, zoon, "animal" + λόγος, "logos", "knowledge") is the branch of biology concerned with the study of animals.

Name

The pronunciation of "zoology" is /zoʊˈɑləʤɪ/; however, an alternative pronunciation is /zuˈɑləʤɪ/. The word zoology originates from the Greek zōon, meaning animal, and logos, meaning study.

Systems of classification

Morphography includes the systematic exploration and tabulation of the facts involved in the recognition of all the recent and extinct kinds of animals and their distribution in space and time. (1) The museum-makers of old days and their modern representatives the curators and describers of zoological collections, (2) early explorers and modern naturalist travelers and writers on zoo-geography, and (3) collectors of fossils and palaeontologists are the chief varieties of zoological workers coming under this heading. Gradually, since the time of Hunter and Cuvier, anatomical study has associated itself with the more superficial morphography until today no one considers a study of animal form of any value which does not include internal structure, histology and embryology in its scope.

The real dawn of zoology after the legendary period of the Middle Ages is connected with the name of an Englishman, Edward Edward Wotton, born at Oxford in 1492, who practised as a physician in London and died in 1555. He published a treatise De differentiis animalium at Paris in 1552. In many respects Wotton was simply an exponent of Aristotle, whose teaching, - with various fanciful additions, constituted the real basis of zoological knowledge throughout the Middle Ages. It was Wotton's merit that he rejected the legendary and fantastic accretions, and returned to Aristotle and the observation of nature.

The most ready means of noting the progress of zoology during the 16th, 17th and 18th centuries is to compare Aristotle's classificatory conceptions of successive.

Subfields of zoology

The study of animal life is, of course, ancient: but as 'zoology' it is relatively modern, for what we call biology was known as 'natural history' at the start of the nineteenth century. During the lifetime of Charles Darwin, natural history turned from a gentlemanly pursuit to a modern scientific activity. Zoology as we know it was first established in German and British universities. The institution of zoology training in British universities was mainly established by Thomas Henry Huxley. His ideas were centered on the morphology of animals: he was himself the greatest comparative anatomist of the second half of the nineteenth century. His courses were composed of lectures and laboratory practical classes; and his system became widely spread.

There was much left out by Huxley, especially the study of animals in their environment, which had been the main stimulus for both Darwin and Alfred Russel Wallace (who both came up with the idea of natural selection). The fact that neither Darwin nor Wallace ever held a university teaching post may have contributed to this rather startling omission. Gradually Huxley's comparative anatomy was supplemented by other much-needed methods. The field of zoology in the twentieth century mainly comprised these approaches:

1. Comparative anatomy studies the structure of animals.
2. The physiology of animals is studied under various fields including anatomy and embryology
3. The common genetic and developmental mechanisms of animals and plants is studied in molecular biology, molecular genetics and developmental biology
4. Ethology is the study of animal behavior.
5. The ecology of animals is covered under behavioral ecology and other fields
6. Evolutionary biology of both animals and plants is considered in the articles on evolution, population genetics, heredity, variation, Mendelism, reproduction.
7. Systematics, cladistics, phylogenetics, phylogeography, biogeography and taxonomy classify and group species via common descent and regional associations.
8. The various taxonomically-oriented disciplines such as mammalogy, herpetology, ornithology identify and classify species, and study the structures and mechanisms specific to those groups. Entomology is the study of insects, by far the largest group of animals.
9. Palaeontology, including all that may be learnt of ancient environments.

Notable zoologists

In alphabetical order by surname:

See also

Sources and external links

• A Study Guide to Invertebrate Zoology ~ at Wikibooks
• Online Dictionary of Invertebrate Zoology
• An online dissection pictures of animals
• Dictionary.com's discussion of pronunciation
• Bizarre zoology news

References