By Wilson da Silva
SYDNEY – Infanticide, murder, racism, adultery, war, rape, genocide – far from being aberrant human traits, they are natural and shared with many other animals.
So says a new book by an American biologist which uncovers some uncomfortable facts about human nature and has been hailed by some scientists as ground-breaking.
“Murder goes a long way back,” author Professor Jared Diamond of the University of California told Reuters. “Chimps practise it. The only difference is that we do it a lot more efficiently. The murderous impulses themselves, they’re something we inherit.
“The commonest cause of death in male adult gorillas is to get murdered by another male gorilla. One of the commonest causes of death for a baby gorilla is to get murdered by a male gorilla that has just killed the father of the baby,” he said.
Diamond’s book suggests that humans have not evolved very far beyond the nasty traits of their distant evolutionary cousins.
He said tests had found there was only a 1.6 per cent sliver of difference between our genes and those of the two species of murderous and genocidal chimpanzees, despite humans and chimps parting evolutionary ways some seven million years ago.
Compared with the gorillas, our genes diverged by only 2.3 per cent, said Diamond, who has just wound up a national tour organised by Sydney’s Australian Museum.
This was a smaller difference than that between the willow warbler and the chiff-chaff warbler, two very similar European birds, Diamond said.
The book says a visitor from outer space would conclude humans are a slightly different form of chimpanzee. Hence the name of the book – The Rise and Fall of the Third Chimpanzee, which won this year’s Rhone-Poulenc Science Book of the Year award in Britain.
Like Desmond Morris and his The Naked Ape bestseller of the 1960s, 54-year-old Diamond studies humans as animals to gain insights which our culture and human “common sense” have obscured.
“What he’s done with his book is pull together an overview of humanity, warts and all, (especially) relying on the huge advances of the last five years,” said Dr Tim Flannery, the Australian Museum’s senior research biologist, who was full of praise for the book and its author.
The book says war, rape, infanticide, racism and genocide are all parts of our past that were practised often.
“Rape is common in orang-utans and ducks. Groups of male ducks gang-rape a female, often injuring the female in the process. Among orang-utans, sex is either consensual or rape sex,” Diamond told Reuters.
In mammals, the bigger the male compared with the female, the more polygamous he is, whereas if both are the same size, monogamy rules.
The slightly larger frame and body muscle of men compared with women suggests humans are largely monogamous but have a tendency toward extramarital sex, the book says.
Parentage studies of babies in Britain and the United States back this up – a surprising 10 to 30 per cent of births looked at were of blood groups that could not have resulted from anything but adultery, the book says.
War is also common in the animal world, his research shows.
“Almost any animal species that has the physical capabilities to murder does it. Not just murder, but mass murder – there’s war between prides of lions, packs of wolves and neighbouring troops of chimpanzees,” Diamond said.
In the late 1970s, biologists in the wilds of Africa watched with horror over years as a troop of chimpanzees made war on a competing group and, one by one, exterminated all the males.
“It’s inefficient – they didn’t have rockets, atomic bombs or spears. The only way they could kill was for six chimpanzees to jump on a single chimp and beat him for half an hour. Those are the animal precedents for human war,” Diamond said.
Studies also show humans tend to mate with those most similar to themselves – not just in religious, political and cultural ways, but in physical attributes such as eye and lip shapes.
Humans with similar characteristics inherently club together and label those not like them as outsiders. This is a tribal, animal instinct and is the root of racism, Diamond’s book says.
He argues that by acknowledging the origins of our darker selves, we better learn to deal with them. We are much less barbaric now than we ever have been, he says.
“You can say war is in our genes, but like murder, rape and infanticide, it’s something society can choose to suppress,” he told Reuters.
“In traditional societies, murder is widespread. But in the 20th century, despite two world wars, far fewer people have died violent deaths than regularly as a result of murder in traditional societies.”