Mammal-like Reptiles Named Tritylodontids Survived 30 Million Years Longer Than Previously Thought

Posted on April 25, 2016

A group of mammal-like reptiles known as the tritylodontids were a hardier animal than originally believed. Recently discovered fossilized teeth indicates the animals were around for 30 million more years than previously thought.

The fossilized tritylodontid teeth were discovered in Kuwajima, Japan. They are the first such teeth found in Japan. It was previously thought the creatures were wiped out when mammals emerged. The new evidence indicates the tritylodontids co-existed with the earliest mammal species for millions of years.

Study author Hiroshige Matsuoka at Kyoto University says in a statement, "They had pretty much the same features as mammals -- for instance they were most likely warm-blooded -- but taxonomically speaking they were reptiles, because in their jaws they still had a bone that in mammals is used for hearing."

Tritylodontids lived in the Jurassic era and proliferated worldwide. They were believed to have gone extinct as herbivorous mammals took over. The fossilized teeth indicates the tritylodontids lived at 30 million years longer than what paleontologists had believed.

Matsuoka says, "This raises new questions about how tritylodontids and their mammalian neighbors shared or separated ecological roles."

A research paper on the finding was published here in the Journal of Veterbrate Paleontology.

ANIMALS