While older 2D fossilised hairs are known, those preserved in the amber are the oldest 3D specimens known.
The hairs, found alongside a fly pupa in amber uncovered in southwest France, are remarkably similar to hair found on modern mammals.
That implies that the shape and structure of mammal hair has remained unchanged over a vast period of time.
“We have 2D hair imprints as early as the Middle Jurassic,” says Dr Romain Vullo of the University of Rennes, France, who discovered the hair.
The Jurassic Period lasted from 200 to 145 millions of years ago, followed by the Cretaceous Period which lasted to 65 million years ago.
“However, carbonised hair provides much less information about the structure than a 3D hair preserved in amber,” says Dr Vullo.
“Our specimens are the oldest known hair specimens in which we can observe the cuticular structure.”