Proboscidea

The Proboscidea (from the Greek προβοσκίς and the Latin proboscis) are a taxonomic order of afrotherian mammals containing one living family (Elephantidae) and several extinct families. This order, first described by J. Illiger in 1811, encompasses the trunked mammals.[1] In addition to their enormous size, later proboscideans are distinguished by tusks and long, muscular trunks; these features were less developed or absent in the smaller early proboscideans. Beginning in the mid-Miocene, most members of this order were very large animals. The largest land mammal today is the African elephant weighing up to 10.4 tonnes with a shoulder height of up to 4 m (13.1 ft). The largest land mammal of all time may have also been a proboscidean: Palaeoloxodon namadicus, which may have weighed up to 22 t (24.3 short tons) with a shoulder height up to 5.2 m (17.1 ft), surpassing several sauropod dinosaurs (in height).[2]

Proboscidea Temporal range: Middle Paleocene-Holocene 60.0–0 Ma PreЄ Є O S D C P T J K Pg N
African bush elephant, Loxodonta africana
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Clade:	Tethytheria
Order:	Proboscidea Illiger, 1811
Subclades
†Eritherium †Moeritherium †Saloumia †Plesielephantiformes Elephantiformes

The earliest known proboscidean is Eritherium,[3] followed by Phosphatherium,[4] a small animal about the size of a fox. These both date from late Paleocene deposits of Morocco.

Woolly mammoth and American mastodon

Proboscideans evolved in Africa, where they increased in size and diversity during the Eocene and early Oligocene. Several primitive families from these epochs have been described, including the Numidotheriidae, Moeritheriidae, and Barytheriidae, all found exclusively in Africa. The Anthracobunidae from the Indian subcontinent were also believed to be a family of proboscideans, but were excluded from the Proboscidea by Shoshani and Tassy (2005)[5] and have more recently been assigned to the Perissodactyla.[6] When Africa became connected to Europe and Asia after the shrinking of the Tethys Sea, proboscideans began to migrate into Eurasia, and some families eventually reached the Americas. Proboscideans found in Eurasia in addition to Africa include the Deinotheriidae, which thrived during the Miocene and into the early Quaternary, Stegolophodon, an early genus of the disputed family Stegodontidae; the diverse family of Gomphotheriidae, such as Platybelodon and Amebelodon; and the Mammutidae, or mastodons.

Most families of the Proboscidea are now extinct, including all proboscideans that lived in the Americas, Europe, and northern Asia. Many of these extinctions occurred during or shortly after the last glacial period. Recently extinct species include the last examples of gomphotheres in the Americas, the American mastodon of family Mammutidae in North America, numerous stegodonts once found in Asia, the last of the mammoths throughout the Northern Hemisphere, and several species of dwarf elephants found on various islands scattered around the world.[7]