In Depth Astrohippus is one of many of the horse genera that were roaming around North America during the Miocene period, but it is one of the few to be considered a close relative of the Equus genus which is where modern horses belong, though the tooth structure of Astrohippus strongly suggests that Astrohippus is … Read more
In Depth Ancylotherium may have been an atypical chalicothere with short hind legs, long fore arms, sloping back and horse-like head, but it was one of the few that did not walk upon its knuckles. Most other chalicothere genera walked on their knuckles to avoid damaging their long claws which they used to hook around … Read more
In Depth Although not a very well-known amphicyonid, Drassonax does help to reinforce the image of the earlier bear dogs being very small predators that were second to creodont mammals like Hyaenodon during the Oligocene. Ultimately however the creodonts did not adapt to changing climatic conditions which drove the development of new prey types, and … Read more
In Depth Although the name means ‘snout horse’, Rhynchippus was actually a notoungulate, a group of South American mammals completely unrelated to horses. Rhynchippus was actually an early relative to the much larger Toxodon that would appear much later around the Pliocene/Pleistocene eras. The similarity between Rhynchippus and primitive horses like Mesohippus is a case … Read more
In Depth Natchitochia is a genus of protocetid whale that lived in waters around North America during the mid-Eocene. Though only known from a few vertebrae and partial ribs, it is known that Natchitochia would have been similar to genera such as Eocetus, Pappocetus and Protocetus. Comparison to the vertebrae of Eocetus and the ribs … Read more
In Depth The many individuals of Palaeotherium recovered from Eocene era deposits in Europe indicate that it was one of the most common mammals across Europe (especially the Western portion) during this time. When first described by Georges Cuvier, Palaeotherium was thought to be related to the ancient Tapirs, but today it is more widely … Read more
In Depth Originally though to be a member of the Archaeoceti, Kekenodon has more recently been considered to be a mysticetid (baleen) whale. Unfortunately the fragmentary nature of the holotype fossils makes is hard to be certain of distinct physical features about Kekenodon. Further Reading - Notes on New Zealand Cetacea, recent and fossil. - … Read more
In Depth Necrolestes is only known from partial remains, but the snout (the best preserved part) has an upturned tip. This has led to speculation that Necrolestes may have had a fleshy appendage similar to that seen on the star nosed mole (Condylura cristata). This in turn has led to speculation that Necrolestes may have … Read more
In Depth Togocetus is a genus of primitive whale that was first discovered in a phosphate mine that is early Eocene in age. Togocetus is noted for being similar to genera such as Protocetus and Pappocetus. Further Reading - A new archaeocete and other marine mammals (Cetacea and Sirenia) from lower middle Eocene phosphate deposits … Read more
In Depth Although details are uncertain, Kutchicetus is noted as being a small remingtonocetid whale (relative of Remingtonocetus). The tail of Kutchicetus seems to have been quite well developed and may have played a more important role in swimming than other primitive whales, though there is no evidence that a tail fluke had been developed. … Read more