AILSA CHANG, HOST:
Bonobos, like chimpanzees, are one of our closest living relatives. We share about 99% of our DNA. These endangered apes are covered in incredibly black hair.
LIRAN SAMUNI: And what's very nice is that they have extremely pink lips, almost as if they put the lipstick on.
SACHA PFEIFFER, HOST:
That's Liran Samuni, a primatologist at Harvard University. Now her team has discovered that wild bonobos share more than just DNA with humans and chimps. They also appear to share our penchant for culture.
SAMUNI: We already had some information about chimpanzees that they have the ability for culture. But it was always this kind of a puzzle about bonobos.
CHANG: So for more than four years, the researchers tracked two bonobo groups in the Democratic Republic of Congo, documenting the apes' social interactions and what they hunted. And they found a striking dietary difference.
SAMUNI: So we had one group which specialized on the hunting of a small antelope called duiker, while the other bonobo group specialized on the hunting of anomalure, which is a gliding rodent.
PFEIFFER: Samuni says think about it in the context of humans. You might have two cultures living near or among each other, but one prefers chicken; the other prefers beef.
CHANG: Samuni's colleague at Harvard Martin Surbeck says that's important because it shows that the two groups of bonobos have different preferences despite their overlapping range.
MARTIN SURBECK: Two groups of the same species which live at the exact same place, you know, which basically hunt at the same place do not hunt the same prey.
PFEIFFER: And that, they say, is suggestive of culture. The details are in the journal eLife.
CHANG: Amy Parish, a primatologist at the University of Southern California, specializes in bonobo behavior. She says she's seen cultural traits in captivity.
AMY PARISH: In San Diego, the bonobos - when they're grooming each other, they take these little pauses where they clap their hands or their feet together. And then they keep grooming. And they alternate between this clapping and this grooming.
PFEIFFER: But Parish says she was intrigued to learn that wild bonobos living in the same forest had such a strong cultural division.
PARISH: Perhaps it helps with group identity in some way. Oh, we don't eat those flying squirrels. We only eat duikers.
PFEIFFER: And the implications of the work go far beyond bonobo culture, Samuni says.
SAMUNI: I think it's almost like, you know, the missing puzzle piece in this story because if we confirm that both our closest living relatives have the capacity, I think it's a much stronger evidence that our ancestors - our common ancestors already expressed some culture.
CHANG: And it's also another reminder that we humans aren't quite as unique as we think we are.
(SOUNDBITE OF BONOBO'S "ANIMALS") Transcript provided by NPR, Copyright NPR.