Field notes on weekend trip to Costa Rica (with disc-winged bats!)

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!)

New paper: risk exaggerates nepotism in vampire 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

Social inheritance in vampire food-sharing networks?

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?

Non-maternal allogrooming of pups

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

What can vampire bats teach us about human cooperation?

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?

Is the ingroup-outgroup bias just two points on a social distance spectrum?

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?

New review of bat cooperation

Most of the 1,300 species of bats live in groups. Indeed, some are quite social, with relationships that last for years. For the latest issue on the evolution of direct benefits cooperation in Philosophical Transactions B, Jerry Wilkinson was asked to write a review on cooperation in bats and he co-wrote the article (PDF) with Kisi Bohn, and Danielle … Continue reading New review of bat cooperation

How we define “reciprocity”: the good, the broad, and the ugly

I hope this is the last blogpost I ever write about semantics. I always want to point people to a good reference on what the words that I use mean (and there isn't a short quick guide), and Wikipedia does not work here. People use the terms "reciprocal altruism" and "reciprocity"in very different ways in … Continue reading How we define “reciprocity”: the good, the broad, and the ugly

VampCam featured at Smithsonian and some recent papers

The VampCam is being featured on the STRI website frontpage. There's an inaccuracy though-- it gives the wrong name of the authors on the study they discuss. I did that social grooming study in collaboration with the Organization for Bat Conservation and co-author Lauren Leffer, an undergraduate at the University of Maryland. I've been in Gamboa, … Continue reading VampCam featured at Smithsonian and some recent papers