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Perissodactyla
Order: Perissodactyla
Families:
Species:
Hoofed mammals are divided into two orders; the Artiodactyla (even-toed ungulates) and the Perissodactyla (odd-toed ungulates). Although superficially similar, the two are not closely related but are nevertheless frequently grouped together under the name ungulates (hoofed mammals). The Perissodactyla include families such as the Equidae (horses), the Rhinocerotidae (rhinoceros) and the Tapiridae (tapirs). Horses have a single toe on each foot whereas Rhinos and tapirs have three toes. Most rhinos and all tapirs live individually, whereas all horse, zebra, ass and the onager live in groups. Ungulates are the most dominant terrestrial herbivores and have become such a highly successful group due to their speed and endurance. Their limbs are embedded within the body wall as far down as the elbow or knee joint. This increased lower limb plus the increased movement in the shoulder joint allow the ungulates to have an extremely long stride length which in turn gives more speed when running. Most large predators will give up a chase if the ungulate manages to outrun them for only relatively short periods of time as carnivores overheat quickly and have low endurance levels. The artiodactyls and perrisodactyls also have fewer toes, thus fewer muscles and tendons which in turn decreases the amount of energy required to move quickly. Unlike predators, ungulates run on their toes, which are encased in sturdy hooves.
Example Species:
Buchell's zebra
Equus burchelli
Length: 2.2-2.5 m
Weight: 175-385 kg
Social unit: Group
Region: East and southern Africa
Status: Lower risk
White rhinoceros
Ceratotherium simum
Length: 3.7-4 m
Weight: Up to 2.3 tonnes
Social unit: Group
Region: West, East and southern Africa
Status: Lower risk
Przewalski's wild Horse
Equus przewalksii
Length: 2.2-2.6 m
Weight: 200-300 kg
Social unit: Group
Region: West, Central and South Asia
Status: Extinct in the wild
Author: Emma-Louise Nicholls
Last updated: 20th November 2005
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