Chimpanzees recognize each other from their buttocks just like humans recognize faces, finds neuropsychologists based on a study of humans and chimpanzees tested with photos of faces and buttocks, both upright and inverted.

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Chimpanzees recognize each other from their buttocks just like humans recognize faces, finds neuropsychologists based on a study of humans and chimpanzees tested with photos of faces and buttocks, both upright and inverted.