Early mammals were not as flashy as dinosaurs and pterosaurs when it comes to their feathers and fur. A new study has found that all six early mammal species that lived during the Jurassic and Cretaceous periods had greyish-brown fur. Researchers, led by Matthew Shawkey at Ghent University in Belgium, analyzed melanosomes – tiny organelles containing pigment melanin – in 116 living mammals to develop a model predicting fur color based on melanosome shape.
The team applied this model to six fossils of different early mammal species, all from the same Chinese deposits but dating back to between 165 and 120 million years ago. One of the newly discovered gliding mammals, Arboroharamiya fuscus, lived around 159 million years ago. As these nocturnal mammals likely needed camouflage to avoid predators like dinosaurs, their subdued colors make sense.
Interestingly, the team found that the fur colors were more similar than predicted, with no significant variations among the species. Shawkey attributes this to their expected dull appearance, noting that many mammals became active during the day after the dinosaur extinction 66 million years ago, leading to more diverse color patterns. The study aims to expand its scope by examining additional early mammal fossils from around the world.
Source: https://www.newscientist.com/article/2472027-fossils-reveal-what-the-fur-of-early-mammals-looked-like