海角大神

Behold the听bonobo, our ape cousin that's kinder and gentler than the chimp or, well, us. Now scientists have mapped the primate's DNA, and some researchers say that may eventually reveal secrets about how the darker side of our nature evolved.

Scientists have found that we are as close genetically to the peace-loving but little-known听bonobo听as we are to the more violent and better understood chimpanzee. It's as if they are siblings and we are cousins, related to them both equally, sharing some traits with just听bonobos听and other characteristics with just chimps.

Bonobos听and humans share 98.7 percent of the same genetic blueprint, the same percentage shared with chimps, according to a study released Wednesday by the journal Nature. The two apes are much more closely related to each other 鈥� sharing 99.6 percent of their genomes 鈥� said study lead author Kay Prufer, a geneticist at the Max Planck Institute in Germany. "Humans are a little like a mosaic of听bonobo听and chimpanzee genomes."

Bonobos听and chimps have distinctly different behaviors that can be seen in humans, with听bonobos听displaying what might be thought of as our better angels, said Duke University researcher Brian Hare.听Bonobos听make love, not war. Chimps have been documented to kill and make war.听Bonobos听share food with total strangers, but chimps do not.听Bonobos听stay close to their mothers 鈥� who even pick out their sons' mates 鈥� long after infancy like humans. But chimps tend to use tools better and have bigger brains, like humans.

"Is the听bonobo听genome the secret to the biology of peace?" asked Hare, who was not involved in the new research. "They have done something in their evolution that even humans can't do. They don't have the dark side we do.

"If we only studied chimps, we'd get a skewed view of human evolution," he said.

Bonobos, chimps and humans shared a single common ancestor from about 6 million years ago, Prufer said. Chimps and bonobos听shared the same common ancestor until about a million years ago, when the Congo River formed. Then the听bonobos developed on one side of the river, the chimps the other. They became different species, even though scientists didn't realize that until about 90 years ago.

Bonobo听heads are slightly smaller and their teeth are arranged differently. In behavior,听bonobos听are far more tolerant, more social. They are inordinately sexual. Instead of releasing tension by fighting, they couple repeatedly, Hare said.听Bonobos听are ruled by alpha females, chimps by males.

In some ways 鈥� especially when looking at the physiology of the brain 鈥� it's as if a听bonobo听is a juvenile chimp that doesn't develop, Hare said. Chimps get more violent as they age;听bonobos听don't.

While the scientific name for听bonobos听is Pan paniscus, "they should be Peter Pan," Hare said. "They never grow up and we have lots of data to support this idea. Much of their psychology seems to be frozen."

Some researchers say Hare has romanticized the听bonobo听too much. Emory University researcher Bill Hopkins says he has more听bonobo听scars than chimp scars on his body. Sure,听bonobos听will bite, but they won't kill, Hare said.

Bonobos听are endangered and only live around the war-torn Democratic Republic of Congo. "Ironically," Hare said, "bonobos are from the place where people are at their worst."

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