All’s fair between chimps? Psychologist Darby Proctor of Yerkes National Primate Research Center in Lawrenceville, Ga., and her colleagues say chimpanzees tend to react in a way that recognizes fairness. “Humans and chimpanzees show similar preferences in dividing rewards, suggesting a long evolutionary history to the human sense of fairness,” Proctor said.
However, other researchers claim that the chimps in the study “interacted little with each other and showed no signs of understanding that some offers were unfair and could be rejected.”
Josep Call and Keith Jensen co-authored previous studies where chimps “generally shared as little as possible with partners, who accepted most offers.”
Does Proctor’s new study, which compares the actions of her chimps with those of pre-school aged kids, prove that fairness can transcend species lines? Do humans even play fair anyway?
Primatology Lesson of the Day #42: West Side Chimps
Pan troglodytes verus, the subspecies of chimpanzees living in western Africa, are considered very special by certain primatologists. Groups of these apes have been documented doing things that are more commonly thought of as early-human-ancestor behaviors than as habits of the great apes. For example, versus has been documented making spears to hunt monkeys, using caves as shelter, foraging and traveling at night, living in a savannah setting, and being fond of playing in water.
Some researchers think the subspecies should be reclassified as a new species of pan, making it the third in the genus, alongside chimpanzees and bonobos. With about 500,000 years of separation from eastern and central chimps (as opposed to the 875,000 between chimpanzees and bonobos and the 100,000 years between eastern chimpanzees and central chimpanzees) it’s not such a crazy idea, but it depends on the definition of species that is used. Since versus can still interbreed with any other subspecies, it is up to scientists to decide if the behavioral and genetic differences are enough. Regardless, the discovery of such variation among chimpanzees is huge and will allow us to further understand our own past.
For anyone interested there’s this short documentary (about 50 minutes long) on hulu about chimpanzees.
Great ape habitat in Africa has dramatically declined
Great apes, such as gorillas, chimps and bonobos, are running out of places to live, say scientists.
They have recorded a dramatic decline in the amount of habitat suitable for great apes, according to the first such survey across the African continent.
Eastern gorillas, the largest living primate, have lost more than half their habitat since the early 1990s.
Cross River gorillas, chimps and bonobos have also suffered significant losses, according to the study.
Details are published in the journal Diversity and Distributions.
