Naturalist Charles Pickering was the librarian and a curator of the Academy of Natural Sciences. In 1843, he traveled to Africa and India to research human races. In 1848, Pickering published Races of Man and Their Geographical Distribution, which enumerated eleven races.
It lived from 98 to 83 million years ago, separating itself from the Velociraptor by roughly 10 million years. You might say it's an ancestor of the actual Velociraptor, even though the original specie of raptor was almost the size of modern chicken and the Achillobator was roughly 1 ft taller than the average person.
The theropods most closely related to avians generally weighed between 100 and 500 pounds â giants compared to most modern birds â and they had large snouts, big teeth, and not much between the ears. A velociraptor, for example, had a skull like a coyoteâs and a brain roughly the size of a pigeonâs.