What did some ancient animals look like? What color was their fur? For a long time scientists haven’t been able to figure out the answer from the fossils left behind, leaving the task of depicting these ancient animals up to the artistic imagination. However, a team of researchers believe they’ve developed a technique to figure out the true colors of these extinct species with fossils up to 300 million years old.
The researchers realized they’ve been misidentifying some leftover microscopic structures. What researcher thought were fossilized bacteria are actually melanosomes. These organelles are found in animals and are responsible for the storage and transport of melanin — a light-absorbing pigment. In short: melanosomes are responsible for giving animals their colors.
By studying the structures of melanosomes in modern-day animals and marine life, researchers have been able to identify colors in ancient mammals, said Caitlin Colleary, a doctoral student of geosciences in the College of Science at Virginia Tech.Â “They all preserve melanin,” she explained, “so it’s safe to say that melanin is really all over the place in the fossil record. Now we can confidently fill in some of the original color patterns of these ancient animals.”
Jakob Vinther, a molecular paleobiologist at the University of Bristol, told Phys.org that these melanosomes are distinct in their shape and chemical make up. For instance, “reddish melanosomes are shaped like little meatballs, while black melanosomes are shaped like little sausages and we can see that this trend is also present in the fossils.”Â Researchers have also worked on finding out how the melanin might become chemically altered over time. In the study, researchers subjected modern hair and feather samples to the high temperatures and pressures fossils would undergo.
“It was important to bring microchemistry into the debate,”Â explained Roger Summons, the Schlumberger Professor of Earth Science at the Massachusetts Institute of Technology, in an interview with Phys.org, “because discussion has been going on for years over whether these structures were just fossilized bacteria or specific bodies where melanin is concentrated.”
Knowing the color of these ancient mammals will help researchers piece together how some animals evolved over time. Summons says that “color is a factor in how individuals recognize and respond to others, determine friend or foe, and find mates.” It’s another piece to the history of animal life.
Image credit: Dallas Krentzel/Flickr