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A mammal (from Latin mamma 'breast') [1] is a vertebrate animal of the class Mammalia ( / məˈmeɪli.ə / ). Mammals are characterized by the presence of milk-producing mammary glands for feeding their young, a neocortex region of the brain, fur or hair, and three middle ear bones.
Marine mammals are mammals that rely on marine (saltwater) ecosystems for their existence. They include animals such as cetaceans ( whales , dolphins and porpoises ), pinnipeds ( seals , sea lions and walruses ), sirenians ( manatees and dugongs ), sea otters and polar bears .
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The Mammals portal. A mammal (from Latin mamma 'breast') is a vertebrate animal of the class Mammalia ( / məˈmeɪli.ə / ). Mammals are characterized by the presence of milk-producing mammary glands for feeding their young, a neocortex region of the brain, fur or hair, and three middle ear bones.
- Molecular Classification of Placentals
- Standardized Textbook Classification
- Mckenna/Bell Classification
- Luo, Kielan-Jaworowska, and Cifelli Classification
- Simplified Classification For Non-Specialists
- See Also
- References
Molecular studies by molecular systematists, based on DNA analysis, in the early 21st century have revealed new relationships among mammal families. Classification systems based on molecular studies reveal three major groups or lineages of placental mammals, Afrotheria, Xenarthra, and Boreotheria. which diverged from early common ancestors in the C...
A somewhat standardized classification system has been adopted by most current mammalogy classroom textbooks. The following taxonomy of extant and recently extinct mammals is taken from the 6th edition of Vaughan's Mammalogy.This approach emphasizes an initial split between egg-laying prototherians and live-bearing therians. The therians are furthe...
In 1997, the classification of mammals was revised by Malcolm C. McKenna and Susan K. Bell. The Classification of Mammals Above the species level, here referred to as the "McKenna/Bell classification", is a comprehensive work on the systematics, relationships, and occurrences of all mammal taxa, living and extinct, down through the rank of genus. T...
Several important fossil mammal discoveries have been made that have led researchers to question many of the relationships proposed by McKenna and Bell (1997). Additionally, researchers are subjecting taxonomic hypotheses to more rigorous cladistic analyses of early mammal fossils. Luo et al. (2002) summarized existing ideas and proposed new ideas ...
The following classification is a simplified version based on current understanding suitable for non-specialists who want to understand how living genera are related to each other. The classification ignores differences in levels and thus cannot be used to estimate the respective distances between taxa. It also ignores taxa that became extinct in p...
Simpson, George Gaylord (1945). "The principles of classification and a classification of mammals". Bulletin of the American Museum of Natural History. 85: 1–350. hdl:2246/1104.Wilson, Don E. and Deeann M. Reeder (eds). (1993.) Mammal Species of the World. Smithsonian Institution Press, 1206 pp. ISBN 1-56098-217-9McKenna, Malcolm C. and Bell, Susan K. (1997.) Classification of Mammals Above the Species Level. Columbia University Press, New York, 631 pp. ISBN 0-231-11013-8Nowak, Ronald M. (1999.) Walker's Mammals of the World, 6th edition. Johns Hopkins University Press, 1936 pp. ISBN 0-8018-5789-9t. e. The evolution of mammals has passed through many stages since the first appearance of their synapsid ancestors in the Pennsylvanian sub-period of the late Carboniferous period. By the mid- Triassic, there were many synapsid species that looked like mammals.
The following is a list of largest mammals by family. Tenrecs and allies (Afrosoricida) [ edit] The largest of these insectivorous mammals is the giant otter shrew ( Potamogale velox ), native to Central Africa. This species can weigh up to 1 kilogram (2.2 lb) and measure 0.64 metres (2.1 ft) in total length. [1] [2]
Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and porpoises. Dolphins and porpoises may be considered whales from a formal, cladistic perspective.
