bonobo

Researchers at Durham University found that chimpanzees were as likely to console one another as bonobos - even though the latter is typically considered the more "empathic" primate.

As one example, chimpanzees and bonobos do not have strict hierarchies based on individuals being male or female, as seen among other primate species.

Scientists now know how many bonobos live in one of the largest pristine tropical forests, a place believed to be the world's stronghold for the endangered species.

Female dolphins, chimps and bonobos are also known to use tools more than their male counterparts, probably for the same reasons.

"They are as different from each other as chimpanzees are from bonobos," said senior author Chris Witt at the University of New Mexico.