According to Karen S. Killmar, Associate Curator of Mammals at the San Diego Zoo,
"Bonobos have been called pygmy chimpanzees in the past, but we now know that
they are a separate species from chimpanzees. Bonobos are great apes
(that also include the chimpanzees and gorillas in Africa, and the
orangutans in Asia) and are found only in a very limited range south of
the Zaire River in the Democratic Republic of the Congo. Bonobos are
probably the most critically endangered of the great ape species."

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