What is the range of the bat coin

31.10.2019 16:01

Through thick and thin: Vampire bats make stable friendships

Dr. Gesine Steiner Press office
Museum of Natural History - Leibniz Institute for Evolution and Biodiversity Research

Friendships are a key source of human happiness, health, and wellbeing. Growing evidence shows that similar relationships are important in other species, including the blood-drinking vampire bat. A team of researchers from the Museum für Naturkunde Berlin (MfN) has discovered that vampire bats form close friendships. These survive even severe stress tests such as the dramatic change from a laboratory environment to the wild. This new study has now been published in the journal Current Biology.

Vampire bats are highly social and cooperative. They choke up captured blood to feed other hungry bats on their social network. They even look after unrelated adult conspecifics, which is particularly remarkable in evolutionary terms. "Researching social interactions in wild vampire bats has been a difficult undertaking in the past and required months and years to observe the bats in their natural habitat," says Simon Ripperger, bat researcher at the Museum für Naturkunde Berlin.

However, the biologists Simon Ripperger and Frieder Mayer from the MfN, together with electrical engineers and computer scientists, have developed a new technology to research the social networks of wild bats. They call them proximity sensors. These are mini-computers that are lighter than a 1-cent coin that biologists attach to every bat like small high-tech backpacks. In this way, all interactions between the bats in the social group are logged. "A few years ago we could only dream of following the social network of wild bats in such detail," says Ripperger, lead author of the study.

This technological advance made it possible for researchers to study the stability of social relationships when the same bats are released back into the wild after a laboratory visit. “For a number of years we have been conducting food-sharing experiments between related and unrelated vampire bats in captivity. However, we also wondered if the stable relationships we are seeing here stem from the unnaturally stable conditions in captivity, "said Gerald Carter Professor of Life Sciences at Ohio State University. Carter, co-author of the study, found that the bats are more likely to share food through being forced together in captivity. “But we wanted to test whether these relationships persist when the bats are back in the wild, where they can freely choose where to fly and which other individuals to interact with Or, to put it another way: Are we dealing with stable social ties that continue in the wild? "

To find out, Carter and Ripperger teamed up. After Carter observed the animals in captivity for almost two years, they fitted a group of bats with proximity sensors and released them back to their original colony in a hollow tree on a cattle pasture in Panama. The sensors collected a huge data set that shows the daily changes in the social networks. "Only with this new type of technology could we show that individuals who clean and feed each other in captivity maintain their social relationships because they get together again in the wild," says Ripperger. But not all relationships could withstand the change of location. “Being close is really important to building social relationships, but it's not everything,” says Carter. “Similar to humans: When you go to university, you make friends with the other students in your dormitory. But after graduation, some of these friendships will continue and others will fade. That can depend on your personality or the individual social experiences that you have had. "

Current Biology, Ripperger and Carter et al .: “Vampire bats that cooperate in the lab maintain their social networks in the wild” https://www.cell.com/current-biology/fulltext/S0960-9822(19)31364- 8 DOI: 10.1016 / j.cub.2019.10.024

Features of this press release:
Biology, information technology, animals / land / forest, environment / ecology
Research results, scientific publications