Artist Rendition of a Tritylodontid (IMAGE) Kyoto University Caption Tritylodontids are the last known family of near-mammalian reptiles, before mammals with features such as advanced hearing evolved. Researchers have uncovered dozens of fossilized teeth in Kuwajima, Japan and identified this as a new species of tritylodontid. This suggests that tritylodontids co-existed with some of the earliest mammal species for millions of years. Credit Seishi Yamamoto/Hiroshige Matsuoka Usage Restrictions Please credit Seishi Yamamoto/Hiroshige Matsuoka License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.