Taxonomy and phylogeny

Elephants belong to the family Elephantidae, the sole remaining family within the order Proboscidea which belongs to the superorder Afrotheria. Their closest extant relatives are the sirenians (dugongs and manatees) and the hyraxes, with which they share the clade Paenungulata within the superorder Afrotheria.[8] Elephants and sirenians are further grouped in the clade Tethytheria.[9]

Three species of elephants are recognised; the African bush elephant (Loxodonta africana) and forest elephant (Loxodonta cyclotis) of sub-Saharan Africa, and the Asian elephant (Elephas maximus) of South and Southeast Asia.[10] African elephants have larger ears, a concave back, more wrinkled skin, a sloping abdomen, and two finger-like extensions at the tip of the trunk.

Asian elephants have smaller ears, a convex or level back, smoother skin, a horizontal abdomen that occasionally sags in the middle and one extension at the tip of the trunk. The looped ridges on the molars are narrower in the Asian elephant while those of the African are more diamond-shaped. The Asian elephant also has dorsal bumps on its head and some patches of depigmentation on its skin.[11]

Among African elephants, forest elephants have smaller and more rounded ears and thinner and straighter tusks than bush elephants and are limited in range to the forested areas of western and Central Africa.[12] Both were traditionally considered a single species, Loxodonta africana, but molecular studies have affirmed their status as separate species.[13][14][15] In 2017, DNA sequence analysis showed that L. cyclotis is more closely related to the extinct Palaeoloxodon antiquus, than it is to L. africana, possibly undermining the genus Loxodonta as a whole.[16]