We are all hardwired to murder, and any one of us could kill if the circumstances were right, a US scientist has claimed.
In a book due to be published later this month, evolutionary psychologist David Buss will argue that homicide has long been a part of human nature, and can be traced back to the "ruthless evolutionary drive to reproduce".
The radical views have already sparked controversy in academic circles.
The Murderer Next Door: Why the Mind is Designed to Kill dismisses traditional assumptions that people are driven to kill by distorting influences such as culture, child abuse or media images.
Professor Buss, who is a professor of psychology at Texas University, argues that murder can be viewed as part of the evolutionary process. His book says that historically killing a foe advanced a man's status and improved his mating possibilities. Murderers' genes triumphed over those of their victims reproductively, transmitting murderous traits to following generations.
The instinct to kill now lies dormant in all of us but can be triggered by events, Professor Buss argues.
"I believe we all have the capability to commit murder," he told The Times Higher .
The book says that 91 per cent of men and 84 per cent of women have had fantasies about killing someone. It draws on a sample of 375 real-life murders and quotes interviews with convicted killers.
Professor Buss said that his book contained "the most penetrating, most comprehensive and most scientifically sound theory of murder ever proposed".
Gloria Laycock, director of the Jill Dando Institute of Crime Science at University College London, said: "Generally speaking we are all capable of committing crime. Most people balk at committing murder. But if you look at Nazi Germany, people who were next-door-neighbours ended up killing each other in the most horrible way. That wasn't because they were horrible people."
But others attacked Professor Buss's theory.
David Canter, professor of psychology at Liverpool University and an expert on crime, said: "I think it's bullshit. The whole attempt to gain some sort of evolutionary explanation for complex human behaviour is little more than pandering to the prurient excitement people get from being told these silly stories."
Steven Rose, the founder of the Open University's brain and behaviour research group, said: "When there are real issues that biologists can have something useful to contribute to, I find these evolutionary fantasies tiresome in the extreme."
He adds: "What evidence is there that murderers leave more children than non-murderers? Did Harold Shipman leave so many?"