This is a very colourful, three-million-year-old mouse.
The exceptionally well-preserved animal, complete with remnant soft tissue, was one of a small number exposed to intense x-ray bombardment by a team led by palaeontologist Phil Manning from the UK’s University of Manchester in a quest to discover the evolution of coat colour in mammals.
By exposing the fossils to x-rays at Stanford Synchrotron Radiation Light Source in the US, and the Diamond Light Source in the UK, the researchers were able to identify traces of pheomelanin, the pigment that turns mammal hair red.
The find, reported in the journal Nature Communications, is significant, because the pigment is unstable and its first appearance in mammals thus unknown. Manning’s brightly coloured fossil comprises the earliest known evidence for its presence.