Ungulate

Ungulate

Ungulates (pronounced /ˈʌŋɡjʊleɪts/) are several groups of mammals, most of which use the tips of their toes, usually hoofed, to sustain their whole body weight while moving. The term means, roughly, "being hoofed" or "hoofed animal". They make up several orders of mammals, of which six to eight survive. Commonly known examples of ungulates living today are the horse, zebra, donkey, cattle/bison, rhinoceros, camel, hippopotamus, tapir, goat, pig, sheep, giraffe, okapi, moose, elk, deer, antelope, and gazelle.

There is some dispute as to whether Ungulata is a cladistic (evolution-based) group, or merely a phenetic group (form taxon) or folk taxon (similar, but not necessarily related), because not all ungulates appear as closely related as once believed. Ungulata, which was formerly considered an order, has been split into:

• Perissodactyla (odd-toed ungulates),
• Artiodactyla (even-toed ungulates),
• Tubulidentata (aardvarks),
• Hyracoidea (hyraxes),
• Sirenia (dugongs and manatees), and
• Proboscidea (elephants).

As a descriptive term, "ungulate" normally excludes cetaceans, which are now known to share a common ancestor with Artiodactyla and form the clade Cetartiodactyla with them. Members of the orders Perissodactyla and Artiodactyla are called the 'true ungulates' to distinguish them from 'subungulates' (Paenungulata), which include members from the afrotherian orders Proboscidea, Sirenia and Hyracoidea.