This order is composed of small mammals called hyraxes. They are plantigrade ungulates, i.e. they have hooves but walk on the tip of their toes. Their front legs have four digits and their hind legs have three digits with pads. In addition, the second digit has a split claw which is used for grooming. These animals have a typical dorsal skin gland with a creamy, odorous secretion produced during the rutting season, as well as continuously growing incisors that form very small tusks.
Hyraxes are similar to pikas and marmots, but are more closely related to elephants and sirenians (manatees and dugongs) in terms of evolution. They share several morphological characteristics with these two groups. These include: the absence of a scrotum in males; the development of tusks from the incisors like those of elephants, whereas they develop from the canines in other mammals; and the presence of flat nails and pads.
Genetic analysis of these species supports the hypothesis that the common ancestor of today’s hyraxes, elephants and sirenians probably evolved in two different ways. One evolutionary branch may have led to present-day hyraxes, while the other may have evolved towards an aquatic lifestyle. The latter may have given rise to the sirenian branch and the Proboscidea (elephants) that returned to terrestrial life.