Research
How cooperative relationships form, persist, and fall apart.
Broadly, I study the causes and consequences of cooperative social behavior. Vampire bats are my study system because they let me do something rare: manipulate cooperation experimentally and watch relationships change in response.
My questions center on reciprocity, fitness interdependence (kinship and group size), partner investment strategies, and the social-network structure of a colony over time.
Ongoing projects
Colony level social relations models
Fitting a STRAND social-relations model across all of our long-term data, separating reciprocity, kinship, and individual generosity in grooming and food sharing, and watching how bonds change over time.
A colony as a directed network — who gives to whom, and how much. Modelled with STRAND (Ross, McElreath & Redhead 2024).
Automatic bat ID with machine learning
Building a computer-vision pipeline to re-identify individual bats from video, testing whether 21 individuals are visually separable on held-out days, so we can study behavior without hand labelling days of footage.
Defection & partner choice
Experimentally manipulating whether a new bat in the colony is helpful or defective, then measuring how bats differentially invest in them: a direct causal test of reciprocity and partner-choice.
Two strangers join the colony
Defection & interdependence
How does response to defection change when bats are also siblings? Or what if they have been long term friends? Or what if the defective bat is their only option? These are all examples of what we might label as “interdependence”, and we want to understand how bats respond to defection differently in these scenarios. The prediction, animated below: after the same defection, an unrelated bat withdraws its investment, while between kin interdependence buffers the response and the focal bat keeps giving.
Unrelated pair
Reciprocal food sharing
Kin pair · siblings
Reciprocal food sharing
From the field to the lab
The bats I study are wild-caught or donated from zoos. The science happens in the lab.
I work with captive colonies of vampire bats: running fasting trials, tracking who shares food with whom, and testing what makes a cooperative bond form and hold. Once the animals are with us, the lab is where they stay. We make sure they are happy and engaged in their new home though! They are well cared for, and often are in better condition than those in the field.
We don’t release vampire bats back to the wild, so the colony has to be a place where bats can live, roost, and socialize naturally enough that the cooperation I measure is the real thing. Good husbandry isn’t a side task: it’s the foundation the entire research program stands on.
Context
Study system
Common vampire bats (Desmodus rotundus), studied in captive colonies (animals that are wild-caught or donated from zoos).
Methods
Bayesian social-relations models (STRAND / Stan), longitudinal network analysis in R, RFID tracking, machine-learning re-ID, and manipulative fasting-trial experiments.
People & support
Advised by Dr. Gerry Carter (Carter Lab), studying cooperation in captive colonies of vampire bats. Earlier training with the Pfennig Lab (UNC) and Sheehan Lab (Cornell).
Five quick answers