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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 .
Mammals by population. Mammalia is a class of animal within the phylum Chordata. Mammal classification has been through several iterations since Carl Linnaeus initially defined the class. No classification system is universally accepted; McKenna & Bell (1997) and Wilson & Reader (2005) provide useful recent compendiums. [1]
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.
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]
List of mammal genera. There are currently 1,258 genera, 161 families, 27 orders, and around 5,937 recognized living species of mammal. [1] . Mammalian taxonomy is in constant flux as many new species are described and recategorized within their respective genera and families.
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.
