Gizmodo reports:

You don’t walk up to a coworker without some sort of greeting, and you don’t end conversations simply by turning heel. There are rules to the game of social behavior, and now a research team studying chimpanzees and bonobos say those great apes have social habits that look a lot like what we humans call “hello” and “goodbye.”

The research team observed over 2,000 interactions between chimpanzees as well as bonobos, another ape species closely related to humans. These salutations and farewells—which occurred about 78% of the time among chimpanzees and 90% of the time among bonobos engaged in cooperative activities—seem to come in the forms of physical contact and locking gazes between individuals, by which the animals party to the shared action can confirm that everyone’s on board. These “joint action phases,” as the researchers call them, seem to be a pretty common aspect of the apes’ social behavior.

“Intriguingly, the pattern mirrored what we find in humans and what some people define as ‘social etiquette’ or ‘politeness’: when interacting with a good friend, you are less likely to put effort in communicating politely. In bonobos, a similar pattern is evident in the structure of the joint action phases,” said Raphaela Heesen, a researcher at Durham University in England and the study’s lead author, in an email. [Continue reading…]