Claim: Sivaladapis, a now extinct primate, did not survive the mass extinction event at the Cretaceous-Paleogene boundary.
Evidence: Roughly 10 million years after the mass extinction event at the Cretaceous-Paleogene boundary that eliminated many organisms, including the non-avian dinosaurs, adapiform primates appear simultaneously in the fossil record of the Holarctic along with many other mammalian lineages that rapidly evolved and diversified. It has been hypothesized that the extinction of Sivaladapis around 8 million years ago was the result of the immigration of leaf-eating colobine monkeys to South Asia, where they directly competed with Sivaladapis.