Scientists from the University of Bristol and the Virginia Polytechnic Institute have just determined the original color of an extinct mammal, specifically two species of prehistoric bats that lived along a lake in the middle of a tropical forest that once existed in Germany.
By studying microscopic structures in the 49 million year old fossils, the two teams concluded that the ancient bats were a reddish-brown in color. Dr. Jakob Vinther, one of the two main researchers on the team alongside Virginia Tech doctoral student Caitlin Colleary, seems to have anticipated the disappointment that the bats were not electric blue. “It might not be a big surprise, but that’s what these 49-million-year-old bats are. They looked perfectly like normal bats,” he said to The Daily Mail. Bummer.
Could be used to identify other colors
The structures that held the key to this discovery have long been a subject of debate. The scientific community was divided as to whether they were organelles that contained melanin, or simply fossilized bacteria that had eaten away at the animal.
Vinther and Colleary used a time-of-flight secondary ion mass spectrometer to study the molecular makeup of the structures and then compared them to modern organelles that contained melanin, also known as melanosomes. They also replicated the conditions under which the bats were fossilized in order to see how the microscopic structures changed during the process.
Vinther first identified the structures as organelles and melanosomes in 2008, having found them in a fossilized feather that he later determined to have been black-and-white striped. The same technique was also used to deduce that a winged dinosaur from China, the Microraptor, had iridescent feathers. (Our fingers are crossed that the name Microraptor means that this animal was a tiny, rainbow colored, flying velociraptor.)
The team also identified distinctions between the two different types and colors of melanin. The reddish brown particles of melanin were shaped, in Vinther’s words, like “little meatballs”, and the black particles were compared to sausages. This distinction could potentially allow scientists to more easily determine the color of all sorts of different fossils.
Colleary described that the range of fossils that they have already determined contain melanin and could be analyzed in the same way as the bat fossils. These fossils include: “fish, frogs, and tadpoles, hair from mammals, feathers, from birds, and ink from octopus and squids.”
This discovery could lead to new developments in scientists’ understanding of evolution, as Colleary points out that identifying the colors of prehistoric animals could also help researchers infer what environment they lived in, how they attracted mates, and even how they protected themselves.