Dr. Michael Sheehan is currently finishing up a Ruth Kirschstein National Research Service Award postdoctoral fellowship in the Museum of Vertebrate Zoology at UC Berkeley working with Prof. Michael Nachman. Next month, he will be starting as an Assistant Professor in Neurobiology and Behavior at Cornell University.
Earlier this spring, Dr. Sheehan gave a talk at UC Davis on his research on “Social recognition, individuality and the maintenance of genetic variation.” While he was here, Ethogram editor Katrina Brock caught up with him to chat about his research and experiences.
The Ethogram: What is the overarching question that you hope to answer with your researcher?
Michael Sheehan: My main interest is [on the] individual, especially the effect of individual recognition on the maintenance of diversity and the patterns of diversity within and between populations. I want to understand how there might be selection for individuals to be distinctive and how that process may lead to patterns of diversification. I’m also interested in the ramifications of individual recognition: How does it effect different types of signal evolution? What are the consequences of individual recognition in terms of learning and memory? How does it impact the whole package of social evolution? I want to think broadly about evolution of social behavior and look at different evolutionary and ecological pressures that give rise to some of the conditions that may favor individual recognition.
TE: You’ve studied facial recognition in both humans and wasps. What are some of the differences and some of the similarities between those two study species?
MS: The basic question is the same: “Why are faces different?” Humans and the wasps that I study use faces for very similar purposes: differentiating between individuals. There are also a lot of parallels. I was able to show that wasps have specialized face learning in the same way that people have specialized face learning. If you look at a picture of a face, the way that your brain processes that image is different from how it would process, for example, an image of a house. There’s actually a special part of the brain that does facial recognition. And there are a bunch fun of quirks. For example, if you turn the face upside down, your brain gets confused and doesn’t recognize it as a face anymore. I didn’t do that exact test on wasps, but I was able to show that they use a similar process. We did some simple types of optical illusions. My research shows that if you change the image a little bit, it tricks the wasp and they can’t discriminate among images as easily. So there are actually a lot of similarities between human and wasp facial recognition.
What was really different between the wasp studies and the human studies was the methodology. My wasp studies involved capturing wasps, painting them with model airplane paint, and watching videos of how they interacted afterward. We caught a bunch of different species of wasps and compared their behavior. On the other hand, the studies with humans actually didn’t require any personal data collection. I mined pre-existing datasets for the information I needed. It was all based on population genomics. These experiments were completely methodologically different. One involved going outside and catching wasps, the other involved spending a lot of time working on the computer. However, in the end, they were answering the same questions. I think one of the things that it goes to show is that you can get answers to the same types of questions by using lots of different types of methods and multiple different systems.
TE: How did your interest in science initially develop?
MS: As a senior in high school, I was inspired by the book Silent Spring by Rachel Carson. The book was a major catalyst for the environmental movement. It is all about the effects of toxins and, in particular, DDT. The book talked about how these pesticides killed frogs and birds. I was interested in biology and the environment and I figured that if I really wanted to do something I had to understand chemistry, that’s the way forward.
TE: How did you transition to the study of social behavior?
MS: I’m one of seven kids and my initial draw to understanding behavior was trying to understand the ideas of personality and birth order. I was interested in how people’s environments shaped them. During my sophomore year, I was taking courses in anthropology that dealt with human evolution. I was especially interested in social behavior. So I took more anthropology courses which lead to me doing undergrad research in human brain evolution and a senior thesis on primate behavior. I just got more and more into it.
I took a year off between undergrad and grad school and went to work on the meerkat project that Tim Clutton-Brock runs. I chose this project because it was a much more experimental paradigm than primatology or human behavior. I also became interested in cooperative behavior and doing experiments to test the fundamental basis of social behavior.
For me, individual recognition seemed like a really interesting complex social problem. That’s one reason why I’ve been working on it and thinking about how individuality evolves. I went through a process of being generally interested in social behavior and then taking one component of it that was more of a package to think about and begin to dissect.
TE: Can you tell us about a fond memory that you have of research?
MS: It’s hard to disentangle the time of your life that something’s happening and what it is specifically. I think that doing fieldwork in general was a lot of fun, both working on the meerkat project and doing my undergrad thesis in Kenya. There was a whole bunch of young people at a field site “running wild,” so to speak, with different animals. It’s not something I’d want to do now necessarily now that I’m older and have a family, but when I was 20, that was really exciting.
TE: What’s a project that you’re excited to do in the future?
MS: One question that I’ve been interested in since starting my dissertation is understanding the genetic basis of facial color pattern variants in the wasps that I study. That’s something that is now tractable to do. I’m going to begin collecting data to start understanding wasp genomics. I am going to collect data in such a way that I can use it to answer lots of different questions including the genetic basis and evolutionary history of these color patterns. That’s one of the big projects that I’m excited about.
Note: Dr. Sheehan is currently seeking postdocs and graduate students. You can contact him here if you are interested.