Joshua StorieDeep in the psychology wing of the Biological Sciences Building, professor Pete Hurd leads the Sex and Violence Lab, where he and his students study evolution, sex, aggression, personality, and survival.
Hurd began his lab in 2001 to study the biological basis of personality, stemming from his work as a field biologist. His lab initially studied aggression levels in lizards and has gone on to study cichlid fishes and humans. Hurd has focused on how genetics, environmental conditions, and prenatal exposure to hormones such as testosterone create aggression and other personality traits.
“There is more than one way of being male and we’re interested in how that comes about,” Hurd said. “That can’t happen if prenatal testosterone exposure is the whole story.”
Numerous research projects have arisen from Hurd’s lab, which include studying how environmental factors influence the sex and behaviour of cichlid fishes throughout life. Hurd is also currently studying how stress early in life influences the cichlids’ personalities and coping styles.
Sex differences, Hurd explained, are shaped by both genetic predisposition and the environment that one grows up in — the common belief that biology is “a mandate that we cannot escape” is a misconception, he said. In his work, Hurd has learned that differences between sexes are not as variant as differences within sexes.
“In continuously varying things like aggression, introversion, extroversion, social skills, and motivation to do social stuff … the differences we find between sexes are about half the size we find between height,” Hurd said. “It’s kind of silly to run around and try to classify all men as huge and women as small, and so as a general rule of thumb, when people start talking about sex differences that’s how big the differences are.”
Hurd said his lab’s work is important in showing that sex exists on a continuum, and does so for evolutionary reasons. Diversity within sexes provides evolutionary advantages to species because less aggressive male organisms may be more unique and valuable in their environment when aggressive males are numerous, and vice-versa.
“It’s akin to extroversion and introversion,” Hurd said. “If you are the only introvert in a population of extroverts, you are doing something useful and valuable and you will gain from it.”
In the lab, Hurd works with cichlid fish that have four different types of males with unique reproductive strategies and aggression levels.
Hurd said he hopes his research will further the notion that sex is not a binary. Some people understand a non-binary system for gender, or the expression of sex, but they may still have a “latent suspicion” that sex remains a dichotomy between male and female. He also said he hopes his research will contribute to understanding autism and schizophrenia in the next five years.
“I hope we contribute to the idea that every single person is on that spectrum and every gene that predisposes someone to developing autism is also a gene that contributes to high IQ,” Hurd said.
