A new fossil specimen of Vilevolodon diplomylos, an ancient herbivore similar to a flying squirrel, may push the origin of mammals back millions of years earlier than previously thought.

Vilevolodon is a haramiyid, an ancient group of animals that lived during the mesozoic era. Until recently they were only known through a few fossilised teeth, but new finds are shedding more light on these enigmatic creatures.

This new specimen features a well preserved middle ear, revealing more advanced structures than had previously been seen. These ear bones could place haramiyids within mammals as a group – settling an argument between palaeontologists and pushing back the origin of mammals to the late Triassic.

Read more on this story: https://www.nature.com/articles/d4158...

Read the paper here: https://www.nature.com/articles/s4158...

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