Mesohippus

Mesohippus
Mesohippus
Temporal range: Early Oligocene
Mesohippus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Perissodactyla
Family: Equidae
Subfamily: †Anchitheriinae
Genus: Mesohippus
Marsh, 1875
Species

M. bairdi
M. barbouri
M. braquistylus
M. equiceps
M. hypostylus
M. intermedius
M. latidens
M. longiceps
M. metulophus
M. montanensis
M. obliquidens
M. proteulophus
M. westoni

Mesohippus (Greek: μεσο/meso meaning "middle" and ιππος/hippos meaning "horse") is an extinct genus of early horse. It lived some 40 to 30 million years ago from the late Eocene to the mid-Oligocene. Like many fossil horses, Mesohippus was common in North America.

Contents

Description

Left: General outline. Center: forelimb bones. Right: a molar tooth (white: cement; dotted: dentine; dark: enamel)

Mesohippus had longer legs than its predecessor Hyracotherium and stood about 60 cm {6 hands} tall. It had also lost a toe and stood predominantly on its middle toe, although the other two were also used.[1] The face of Mesohippus was longer and larger than earlier equids. It had a slight facial fossa, or depression, in the skull. The eyes were rounder, and were set wider apart and farther back than in Hyracotherium.

Mesohippus bairdii skull

Unlike earlier horses, its teeth contained a single gap behind the front teeth, where the bit now rests in the modern horse. In addition, it had another grinding tooth, making a total of six. Mesohippus was a browser that fed on tender twigs and fruit.[1] The cerebral hemisphere, or cranial cavity, was notably larger than that of its predecessors; its brain was similar to that of modern horses.

See also

References

  1. ^ a b Palmer, D., ed (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 255. ISBN 1-84028-152-9. 

External links