When species have babies with conspicuous fur, it can attract good attention—or bad. A new theory could explain why.
THE FIRST THING you might notice about the Delacour’s langur is its color. It’s got a jet black torso, limbs, and head, with a shaggy white butt sandwiched in the middle. (These monkeys—Trachypithecus delacouri if you want to get technical—quite literally look like Oreos.) But that’s just how the adults look. The babies are a different story: They’re orange.
This is their distinct “natal coat,” which fades after a few months. Babies from dozens of other primate species also have fur that’s a different color from that of adults. “One of the big questions has always been why—why would they have distinct coats?” asks Ted Stankowich, an evolutionary ecologist and Director of the Mammal Lab at California State University Long Beach.