"Men lay claim to particular women as songbirds lay claim to territories, as lions lay claim to a kill, or as people of both sexes lay claim to valuables," wrote the evolutionary psychologist Margo Wilson.
Such provocative statements explaining men's proprietary view of female sexuality brought Dr. Wilson and her collaborator Martin Daly international attention and acclaim.
In a career that spanned 30 years, Dr. Wilson, along with her husband and fellow evolutionary psychologist, shed light on why animals - human and non-human - do what they do.
She and her husband were first to study the evolutionary roots of homicide, and to demonstrate that step-parents are more likely to murder their children than biological parents - "the Cinderella effect" - and that cross-culturally, men are more likely than women to kill out of sexual jealousy.
Margo Wilson was born in Winnipeg in 1942. At the age of six, she moved with her mother, a nurse, to the Gwich'in community of Fort MacPherson in the Northwest Territories, where she was educated in a one-room schoolhouse, the only non-first-nations child.
She learned how to trap muskrats to finance the school lunch program, and drove around in a dog sled. She also learned what it feels like to be an outsider.
"Margo was very sensitive to people feeling excluded," said Dr. Daly. "She was always really intolerant of intolerance and liked to encourage people whose situation was genuinely one of outsiderness and disadvantage."
After high school in Victoria, Dr. Wilson attended the University of Alberta, graduating with a degree in psychology in 1964.
During a summer internship in a mental hospital in Oregon, she was disturbed by the conditions patients were kept in, and lost her enthusiasm for the clinical setting.
She later worked in an avian embryology lab, and her scientific focus turned to physiology.
"Being an undergrad in Edmonton," said Dr. Daly, "it was really cold, and every year she and her friends would sit around and count their pennies, to see how far south they could get." This led Dr. Wilson to graduate work in behavioural endocrinology at the sunny University of California.
She won a Commonwealth Scholarship to study at University College London, England, where she earned her PhD in 1972. Of the award, Dr. Daly joked, "That was enough to keep her in cigarettes, which she used to smoke."
While in London, she examined the behavioural effects of castration and hormone replacement in Rhesus monkeys at the Bethlehem Royal Hospital, also known as "Bedlam" - the first and oldest mental institution.
"The experiments were extremely new, the first monkey work of its kind," said Barry Keverne of the department of zoology at the University of Cambridge, who worked with Dr. Wilson in London. "Very few labs in the world were approaching this direction."
Dr. Wilson moved back to Canada and met Dr. Daly in Toronto in 1974, where they were both working at the University of Toronto. By 1975, they met again at an Animal Behavior Society meeting in North Carolina.
"I followed her home back to Toronto, and I wouldn't leave," Dr. Daly said.
The couple moved to Hamilton in 1978, where Dr. Daly got a job at McMaster University.
"Margo had a lot of crap for being a female. When we arrived, I got a job, and Margo was as qualified as I, but in those days there was a no spousal hiring rule, so even when jobs would come up, she wasn't eligible to apply," he said.
In the 1980s, she became a professor in psychology at the university, where she remained until this year.
Dr. Daly added, "She wasn't a feminist in the ranting sense, but she pushed hard about these issues. She became interested in violence against women, who gets assaulted by their husbands and why."
In 1978, Dr. Wilson convinced Dr. Daly that they should investigate homicide, and conduct epidemiological analyses of patterns of risk for violence in different categories of relationships. They pursued this study for the next 30 years and it became their best-known work.
"Most of the homicide research that had been done when we started was done by researchers who were trying to understand differences in homicide rates between places at the societal level," Dr. Daly said. "Nobody was trying to understand the relationship-specific risk patterns."
Together, they several books, and more than 100 academic papers and book chapters.
"Their greatest impact was in the area of understanding motivations behind intimate partner violence," said Holly Johnson, an associate professor in the department of criminology at the University of Ottawa. "They recognized the importance of environment and culture, and helped us to situate evolved psychological mechanisms within social environments and cultures."
In 1987, Dr. Wilson became the first graduate of the masters of studies in law degree program at the University of Toronto. In 1998, she was named a fellow of the Royal Society.
Dr. Daly and Dr. Wilson were the only two people to attend every meeting of the Human Behavior & Evolution Society since its inception. The society honoured Dr. Wilson with a lifetime achievement award this year.
"Margo had done as much as anybody to advance the notion that we can study the social behaviour of human beings within the same framework as studying the social behaviour of any other animal," Dr. Daly said.
Margo Wilson was born in Winnipeg on Oct. 1, 1942. She died in Hamilton on Sept. 24, 2009, of cancer. She was 66. She leaves her husband, Martin Daly.
Margo Wilson co-authored the following books with her husband Martin Daly, also an evolutionary psychologist at McMaster University. Sex, Evolution, and Behaviour (1978) A discussion of theory relating to evolutionary and adaptive aspects of reproductive behaviour, from single-celled organisms to humans. Homicide (1988)
An exploration of anthropological and historical data as a framework for understanding why humans kill. The truth about Cinderella: A Darwinian view of parental love (1998)
Explores evolutionary reasons behind mistreatment of stepchildren, how step-parenthood is different from genetic parenthood and why step-relationships succeed or fail.