Your Daily Fossil

Patriofelis 

Mounted specimen located at the American Museum of Natural History. Not currently on display. Big thanks to Suzann for taking the photo of the mounted skeleton for me! 

Reconstruction by Jay Matternes

When: Eocene (~50 to 45 million years ago)

Where: Western North America

What: Patriofelis is an oxyaenid creodont. Even though its name means ‘father cat’, it is not ancestral to cats at all; any similarity is purely due to convergent evolution. Creodonta is an archaic group of carnivorous mammals, taxonomically separate from modern carnivorans (this is the group that includes cats and dogs). When Patriofelis was stalking its prey, the ancestors of modern big cats were small forms, the largest only about the size of a large house cat.  Patriofelis was one of the first large mammalian predators, at four to six feet (~1.2 to 1.8 meters) long, not counting tail. It was roughly the size of an extant jaguar, but even more powerfully built. It was most likely an ambush predator. Patriofelis was a pure carnivore, all of its molar teeth were laterally compressed into blades, with the lower teeth shearing past the uppers. Living carnivorans also have blade like teeth, called carnassials, but the sheer is restricted to a single pair of teeth. Despite reconstructions, Patriofelis looked different from modern big cats in several major ways beyond just its dentition.  It did not have retractile claws and its head was constructed very differently, as its brain was relatively very small. It should have much more of a ‘flat’ top than it has been drawn with. I would love to see a nice well done reconstruction of this amazing animal. If any of my followers are artists with some free time… ;) 

The relationship of Patriofelis and other creodonts to modern taxa is uncertain. Ferae is the name given to the proposed grouping of creodonts and carnivorans, but in recent years this relationship has been heavily criticized in the literature. The two subgroups of Creodonta (Oxyaenidae and Hyaenodontidae) have also been proposed to have no close relationship to one another, meaning Creodonta itself would be not be a valid group. Much of this criticism however was not born out of any rigorous test of relationships, but rather the assumption that the earliest studies were too heavily based on the meat eating diet of both creodonts and carnivorans, and since each group has a different set of up carnassial teeth, it was concluded this had to be convergence. However, the few very recent studies which have incorporated creodonts and tested their relationships to each other and to the rest of Mammalia have not only upheld a monophyletic Creodonta, but a creodont+carnivoran grouping as well. So don’t count Ferae out yet!