chalicothere

Chalicotheriidae Fossil range: 40–3.5 Ma PreЄ Є O S D C P T J K Pg N middle Eocene to late Pliocene
Moropus elatus at the National Museum of Natural History, Washington, DC
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Perissodactyla Family: †Chalicotheriidae Gill, 1872
Genera
†Ancylotherium †Anisodon †Borissiakia †Chalicotherium †Chemositia †Kalimantsia †Limognitherium †Lophiaspis †Moropus †Nestoritherium †Tylocephalonyx

Chalicotheres (from Greek chalix, gravel + therion, beast) were a group of herbivorous, odd-toed ungulates (perissodactyl) mammals spread throughout North America, Europe, Asia, and Africa during the Early Eocene to Early Pleistocene subepochs living from 55.8 mya—781,000 years ago, existing for approximately 55.02 million years.^[1]

They evolved around 40 million years ago from small, forest animals similar to the early horses. Many chalicotheres, including such animals as Moropus and Chalicotherium, reached the size of a horse. By the late Oligocene, they had divided into two groups: one that grazed in open areas and another that was more adapted to woodlands. They died out around 3.5 million years ago, and are related to the extinct brontotheres, as well as modern day horses, rhinoceroses, and tapirs^[2].

Anisodon grande, formerly Chalicotherium grande.

Description

Unlike modern perissodactyls, chalicotheres had long forelimbs and short hind limbs. Consequently, Chalicotheres probably moved with most of their weight on their short, strong hind legs. Their front legs had long, curved claws indicating they knuckle-walked like giant anteaters today. Fossil remains have shown thick, developed front knuckles, much like gorillas. It was once thought that the claws were used to dig up roots and tubers, however, the wear on the claws and teeth do not suggest that they dug or ate dirt-rich foods such as tubers. The chalicotheres probably used their claws to strip vegetation from trees and to forage for food.

Chalicotheres did not have front teeth in their upper jaw, and their back teeth show little wear, suggesting that they probably were selective browsers^[3].

Cryptozoology

Some cryptozoologists have hypothesised that (the supposedly carnivorous) cryptid from Africa, the Nandi Bear, could be a chalicothere.[1]

See also

• Moropus
• Ancylotherium

References

• Paleobiology Database retrieved on Nov 23, 2007.

External links

• BBC's Nature Fact Files