Bonobos and Chimpanzees

What are the differences and similarities between bonobos and chimpanzees? Although they may look very similar, bonobos and chimpanzees were identified as two distinct species of great ape in 1929. Bonobos have a more slender, gracile build than chimpanzees, who are considered more robust. From birth, bonobos tend to have dark faces with pink lips and hair that often looks as if it were parted down the middle. Chimpanzees, on the other hand, are usually born with light faces that freckle and darken with age.

The two species also differ in aspects of their social behavior and communication. Females of both species leave their natal group at the onset of sexual maturity. However, bonobos are matriarchal - meaning females are in charge of the group. Chimpanzees are patriarchal - with the group being led by a single alpha male. While males form the strongest social bonds in chimpanzees, it is the female-female social bond that is the most important in bonobos. Of the two species, bonobos are the only one to exhibit a unique socio-sexual behavior called genital-genital rubbing or “gg” rubbing. This behavior is thought to ease social tension and promote social bonding among group members.

In regard to communication, bonobo vocalizations have a higher frequency than chimpanzee vocalizations. While bonobos produce tonal sounds in the form of peeps and peep-yelps, chimpanzee vocalizations are noisy and sound much more like grunts and barks. You can see and hear the difference below!

Although they are two distinct species, chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) share a close genetic relationship. Both bonobos and chimpanzees are more closely related to humans than either of them are to the other two species of great apes: orangutans and gorillas. In addition, they both live in highly social, multi-male, multi-female groups - called troops. Chimpanzees and bonobos use complex communicative signals from a variety of modalities - just like we do! As the closest living relatives to humans, bonobos and chimpanzees can help us better understand the evolutionary origins of our own behavior and language.