First mammal emerged alongside the dinosaurs

Mammals evolved 20 million years earlier than previously thought, scientists have discovered, after finding that a small shrew-like creature lived alongside the oldest dinosaurs.

The little animal, named Brasilodon quadrangularis, was found in late Triassic era fossil beds in south Brazil, dating from 225million years ago.

A new study of its teeth by scientists from the Natural History Museum and King’s College London has shown the creature could be the first mammal. Scientists look for evidence of “diphyodonty”, the phenomenon of milk teeth giving way to adult teeth.

The research is published in the Journal of Anatomy.