Monkeys don’t get much more attractive than the red-shanked douc. It looks like it applied a dusting of rouge to its face—a face that is topped by a black cap, flanked by a white beard, and plastered with a permanently innocent expression. From the neck down, it has a black-and-charcoal shirt with a rusty collar, white sleeves, a pair of hipster-red stockings, and a white tail.
Gorgeous. But perhaps slightly less so when you’re running after one, waiting for it to poop.
That’s what Jonathan Clayton from the University of Minnesota did for nine months, in the Vietnamese jungles where the doucs are found. He tracked 66 of them as they scampered through the trees. When they defecated—and for some reason, when one goes, they all go—Clayton and his colleagues ran over to scoop the poop with some pre-labelled popsicle sticks, one for each individual monkey.
Those sticks captured samples of the doucs’ microbiomes—the thriving communities of bacteria and other microbes that live in their guts. And by comparing these wild communities to those of other doucs living in zoos, he could work out how captivity alters the monkeys’ microbes.
This matters because microbiome changes have been linked to many disorders including diabetes, malnutrition, obesity, inflammatory bowel disease, and more. Doctors are increasingly taking note of these connections, and so are vets and conservationists. “Doucs are highly endangered and don’t survive well in captivity,” says Dan Knights, who led the project. “Jonathan wanted to understand how they might be better cared for.”