The world’s oldest fossil skin is 289 million years old and belonged to a reptile: it had a ‘pebble’ structure (photo by Mooney et al./Current Biology) and closely resembles that of modern crocodiles. It was discovered by the work coordinated by the paleontologist Robert Reisz, ofUniversity of Torontopublished in Current Biology in the Richards Spur cave system in Oklahoma and dates back 21 million to the oldest skin remains found so far.
“Finding such an ancient skin fossil is an exceptional opportunity to peer into the past and see what the skin of some of these early animals might have looked like,” said Ethan Mooney, a researcher at the University of Toronto and first author of the study. This type of discovery – he added – can really enrich our understanding and perception of these pioneering animals”. The fossil is a fragment just the size of a fingernail which however has perfectly preserved the entire tissue preserved in the particular environment of the Spur limestone caves inside which the casts of other portions of skin were also found. It was not possible to identify which species of reptile they belonged to but according to the scholars the epidermis found has a pebble structure alternating with more flexible tissues with a hinge function similar to that of modern crocodiles. Rarely tissues like skin end up fossilising, but the researchers believe that in this case the preservation of the skin was possible thanks to the unique characteristics of the cave system, which included fine clay sediments: «the animals would have fallen into this cave system during the Early Permian and would have been buried in very fine clay sediments that would have delayed the decay process,” Mooney added.
