zoology
how zoology is contributed to environmental science
zoologist
Zoology is the area of systematic biology that studies the animal kingdom. Systematic biology (or just systematic) is "the scientific study of the kinds and diversity of organisms"
classification
One of zoology's main purposes is to identify all animals through classification. Classification is accomplished by comparing the characters, or features, of groups of animals. These characters may be of very different nature: morphological characters refer mainly to body structures, whereas histologist and scatological characters are those of body tissues and cells, respectively. The number and forms of the chromosomes (karyology) are also considered a distinctive feature, but methods of DNA complementary ("molecular systematic") are being used increasingly. The presence, absence, or even the structure of certain biochemical compounds are used as characters. Certain physiological functions (for example, temperature regulation) are also considered in classification.
zoological works
Many zoological works published during the nineteenth century included full portraits of the species described, especially of colorful birds, butterflies, and shells. The lavishly illustrated books of the American ornithologist John James Audubon (1785–1851) are among the most famous. Most zoological publications, however, do not include artistic portraits of the species they study, but do have drawings of some details of their morphology, as well as precise written descriptions. The animal specimens on which such descriptions are based are deposited in specialized collections, most of which are kept in natural history museums. The first zoological museum in America was established by Charles Wilson Peale (1741–1827); it opened at Independence Hall, Philadelphia, in 1786. Peale's museum eventually incorporated many specimens collected by the Lewis and Clark Expedition (1804– 1806).