Female vampire bats regurgitate bloody dinners for their starving girlfriends

Female vampire bats regurgitate bloody dinners for their starving girlfriends

Grace Wade

A study published on Halloween in Cell Biology found that vampire bats develop and maintain social bonds resembling friendships. Biologists knew these creatures were uniquely hospitable with one another due to their rare grooming and food-sharing habits. But until now, scientists had been unable to prove they formed long-standing relationships.

Researchers Gerald Carter, an associate professor at Ohio State University, and Simon Ripperger, a postdoctoral fellow with the Smithsonian Institute, hypothesized that bonds between bats developed during captivity would continue after they were released back into the environment. For the study, the researchers had two groups of bats commingle: one cohort was captive-born and another (200 of them) was from a wild colony.

To induce relations, the scientists fasted each bat one at a time. When a bat is starved of blood for a night their peers will regurgitate last night’s dinner as a “food donation” and comfortingly groom one another. According to Carter, females are the only ones to perform this behavior. (It seems to Carter that males are too concerned with fighting one another over established territories to form friendships.)