Spix's disc-winged bat Thyroptera tricolor has suction cups (yes, suction cups) on its thumbs, and it uses these to cling to the smooth surface of young, furled Heliconia leaves. I’ve wanted to see a disc-winged bat since I was about ten years old, and I finally got to see them this week while visiting Gloriana … Continue reading Field notes on weekend trip to Costa Rica (with disc-winged bats!)
Here's the paper. In evolutionary biology, we often draw a line between "altruism" and other cooperative traits. Altruistic traits are special in that they lead to a net cost to one's survival and reproduction. Some traits are clear cases: when a bee stings you it dies, so the suicidal bee sting is an altruistic trait. But … Continue reading New paper: risk exaggerates nepotism in vampire bats
In 1984, Gerald Wilkinson published a paper in Nature showing that vampire bats share food in the form of regurgitated blood, within groups that contain both kin and non-kin. This was one of the fi… Source: Revisiting Wilkinson 1984
We are soon to be wrapping up several analyses and starting some new ones. I want to mention one analysis that never really got off the ground, but it's a good idea. My intern Jana asked me a great question: Does a female vampire bat inherit some of her food-sharing partners from her mother? This question … Continue reading Social inheritance in vampire food-sharing networks?
We have four new vampire bats. The bats here at the field station have been breeding in captivity, which is a good sign that they are doing well, and it ensures we have some highly related dyads for our experiments. My first intern, Jana, just took this neat video of a mother and her new pup … Continue reading Non-maternal allogrooming of pups
I have been asked this question several times by journalists and people during outreach events. So here's my answer: If you really want to understand human cooperation, you should study humans. Specifically, we should study how humans cooperate with each other under natural circumstances across a wide diversity of cultures. And we should manipulate the … Continue reading What can vampire bats teach us about human cooperation?
Looking into the human literature on the evolution of cooperation, I feel that studies on humans are often conducted and interpreted poorly compared to studies of cooperation in ants, bacteria, fish, and other nonhuman primates. One point of confusion involves wrong assumptions about what individual humans should maximize and how well they should do it. But another … Continue reading Is the ingroup-outgroup bias just two points on a social distance spectrum?