Scientists have noticed that our closest relatives almost always greet each other when they meet, and when parting, they say goodbye.
Almost any meeting and parting between people takes place within the framework of the ritual accepted in society. At the very least, we try to greet each other and say goodbye. The same "hello" and "goodbye" were found in groups of our close relatives - chimpanzees and bonobos (pygmy chimpanzees). This is covered in a new article published in iScience magazine.
Raphaela Heesen and her colleagues at the University of Durham monitored the behavior of captive primates and recorded a total of 1,242 interactions between them. Greetings were noticed in 69 percent of interactions in chimpanzees and 90 percent in bonobos. Farewells are 86 percent of chimpanzees and 92 percent of bonobos. Scientists attribute this to their different social structure: chimpanzees are more hierarchical than bonobos with their almost egalitarian communities. Equality requires more attention to social interactions.
Of course, primates do not use speech and instead exchange touches and long glances in the eyes - as, indeed, humans in some circumstances. “Interestingly, this pattern reflects human behavior that is considered 'social etiquette' or 'politeness,'” says Rafaela Hysen. “When we talk to a good friend, we pay less attention to it, and the same happens with bonobos.”
The duration of such interactions is determined by the relative position in the hierarchy. The closer the individuals are to each other, the shorter the greetings and farewells become. Conversely, in some cases these actions are "lengthened", including holding hands, rubbing heads, sometimes short play, or mutual grooming - combing. However, “polite” greetings and goodbyes are far from the only “human” trait of bonobos. It was recently shown that they empathize and comfort each other in adversity.