A team of paleontologists and biologists has analyzed fossilized fur samples from Mesozoic mammals to determine their coloration. Using a predictive model, they found that all six studied species likely had dark, uniformly dull fur coloring. The researchers used melanosome patterns in fossilized fur samples to make their conclusions. By analyzing patterns in living mammals’ melanosomes, the team created a predictive model to identify pigmentation patterns.
Prior research has shown that melanosomes can reveal the coloration of feathers, skin, and fur. This technique has been applied to dinosaurs, and the researchers wondered if it could be used for mammals as well. The study analyzed 116 living mammals’ melanosome patterns using electron microscopy and spectroscopy before applying the predictive model to six Mesozoic mammal fossils.
The results suggest that dark, uniform coloring may have provided benefits such as thermoregulation or mechanical strength. The researchers note that mammals evolved after the dinosaurs went extinct, filling niches they left behind with diverse skin and fur colors. Small, nocturnal mammals like moles often have dark fur to evade predators.
Source: https://phys.org/news/2025-03-melanosome-patterns-mesozoic-mammals-dark.html