Baboon friends swap gut germs. Duke Today, March 16, 2015. The warm soft folds of the intestines are teeming with thousands of species of bacteria that help break down food, synthesize vitamins, regulate weight and resist infection. If they’re so key to health, what factors shape an individual’s gut microbial makeup? Previous studies have pointed to the food we eat, the drugs we take, genetics, even house dust. Now, a new study in baboons suggests that relationships may play a role, too. Picked up by The Scientist.