The researchers used video of chimpanzees interacting with each other to isolate instances of chimpanzee-to-chimpanzee communication and collect data on which chimpanzee initiated the interaction and how the primates responded with gestures and other behaviors. Overall, the researchers observed more than 8,500 gestures from 252 chimpanzees.
By analyzing the “conversation” patterns, the researchers found that 14 percent of all interactions included an exchange of gestures between interacting chimpanzees. The majority of gestural interactions (83 percent) consisted of a two-step exchange of gesture and gesture. The timing of the chimpanzees’ responses was similar to humans, but it took the animals longer to respond to gestures with other behaviors.
“We found some variation between chimpanzee communities, which is consistent with humans having some cultural differences in the pace of speech, with some people in some cultures speaking slower and others faster,” lead author Gal Badig, a research fellow at the University of St Andrews, said in a news release. release.
Although the timing varies slightly across communities, the similarities to human conversation suggest a “shared mechanism” between humans and chimpanzees, the researchers write. Turn-taking in conversation may have evolved to strengthen social bonds and ensure consistency on both sides of an interaction.
They call for future research into the speech patterns of other animals to understand why and how such norms evolved.