Mesonychid

Live reconstruction of Mesonyx

• Asia
• North America

The Mesonychia are an extinct order of mammals. They were the only real predators among the ungulates. The most common species were Mesonyx and Andrewsarchus. Earlier they were asked as a family Mesonychidae in the order Acreodi. The Mesonychia were long considered the ancestors of whales.

Features

The Mesonychia remembered something about dogs with large heads. Your back teeth were well suited to cut meat, but on her feet she wore instead of claws, as we know it today by predators ago hooves. The earliest types still had five toes on each foot and kicked on with the whole sole. Later as Pachyaena, a Mesonychide from the latest Paleocene had only four toes, and stood on her toes.

Phylogeny

The Mesonychia developed well in the early Paleocene of Asia. One of the first forms is Yangtanlestes. From the middle Paleocene they spread with Dissacus and Ankalagon also on other continents. Dissacus was about the size of a coyote and spread over the entire northern hemisphere, Ankalagon from North America was much larger, his skull was the size of a bear. However, these animals possessed in comparison to body size disproportionately large skull.

In the Paleocene there were three families of Mesonychia that Triisodontidae that Mesonychidae and the little-known Hapalodectidae. The former belonged together with the Arctocyoniden the dominant predators of the first mammalian societies at the beginning of the Tertiary. Triisodontier species such Eoconodon and his successor Triisodon among the largest mammals of the lower and middle Paleocene, as all existing mammals were still quite small. The largest Triisodont was Andrewsarchus from the Middle Eocene of Asia, which is considered the largest carnivorous land mammal of earth's history at the same time. Mesonyx and Pachyaena belonged to the family of Mesonychidae.