Social Microbiome Observed in Vampire Bats

In an unusual study, researchers brought vampire bats from distant Panamanian populations together for four months in a laboratory setting and tracked how the bats’ gut microbes changed over time. Published in Biology Letters, the study revealed that the gut microbiomes of bats became more similar the more often they engaged in social behaviors with one another. Such behaviors included huddling together for warmth, grooming themselves and their neighbors, and—in rare cases—sharing food via regurgitation.

The scientists studied social microbiomes while controlling for other factors such as diet and environment. The study kept all the bats together in one enclosure and the bats consumed the same, laboratory-prepared food: cattle and pig blood. “Vampire bats have these really interesting social behaviors, and their diet is very controlled because they only consume blood,” said lead researcher Gerald Carter. “So, vampire bats are a natural model to explore the relationship between their social behaviors and their microbiomes.” To better understand this dynamic, the team compared the patterns of microbiome variation within, and between, the different groups that were housed together.

“We saw that the microbiomes of bats that regularly engaged with one another socially became more similar to one another,” he said. “When bats interacted less—even if they came from the same population initially—their microbiomes were less similar by the end of the four months.”

The work elucidates how social microbiomes develop and change, and because vampire bats sometimes carry rabies and can spread it to humans and livestock, Carter said. Understanding how microbes are transmitted in these animals may help scientists find interventions to reduce the spread of pathogens like rabies, he concluded.