A tutorial introducing the principles of taxonomy with a focus on human classification categories.
Guide to environmental education resources on the web concerning endangered and extinct species
Developed by the Dept.of Systematic Zoology, at the Smithsonian Museum of Natural History, this site contains the names of the 4,629 currently recognized species of mammals, in a taxonomic hierarchy that includes Order, Family, Subfamily, and Genus.
Mammalian Species is published regularly by the American Society of Mammalogists. Each account summarizes the current understanding of the biology of a single species, including systematics, distribution, fossil history, genetics, anatomy, physiology, behavior, ecology, and conservation. PDF files of the first 631 accounts are now available at this website