Chimpanzees gesticulate as quickly as humans speak
Language is the foundation for human development. But a comparable means of communication could also exist between chimpanzees. This is supported by the research findings of a team that investigated the speed of animal gestures.
In our communication, humans are true reaction artists: when we speak to each other, there is only a fraction of a second between word exchanges. However, the speed of our conversations is not particularly remarkable. A team of researchers found that chimpanzees communicate with each other at a similar rapid pace, but they do not use a verbal language. Instead, they gesture.
"Human languages are incredibly diverse, but a common feature is the structuring of our conversations with rapid word exchanges of approximately 200 milliseconds," explains Cathrine Hobaiter from the University of St. Andrews about the pauses in human conversations. "However, it was still an open question whether this is unique to humans or if other animals also have this structure." The study published in the journal "Current Biology" now shows that this is at least the case with chimpanzees.
Exchange of Animal Gestures
The researchers analyzed a total of 8500 gestures from 252 chimpanzees from five wild chimpanzee groups in East Africa and measured the time between individual gestures in a "conversation." "We found that the timing of gestures from chimpanzees and the word exchanges from humans are similar in speed," explains first author Gal Badihi. This suggests that similar evolutionary mechanisms were at work in the development of social interaction in both species. Another theory of the team is the possibility that the high speed developed independently in humans and chimpanzees as a communication strategy.
The ability to have quick conversations, the research group sees primarily as a way to greater efficiency in coexistence. Since for a quick exchange less time and energy is required, common and individual goals could be achieved more quickly and with less effort, assume the authors.
Fine Differences between Chimpanzee Cultures
Even cultural differences made the researchers curious. Just as people in different countries have different pause lengths between word exchanges, the reaction speed of chimpanzees in gesturing varied minimally between groups. "Fascinatingly, they seem to share both our uniform timing and the fine cultural differences with us," says Hobaiter. "Among humans, it's the Danes who are 'slower' in responding, and among East African chimpanzees, it's the Sonso group in Uganda."
However, the conversations of humans and chimpanzees differ significantly in content, according to the researchers. Chimpanzee gestures primarily serve as calls to action, while in our conversations, humans have a much more complex meaning repertoire at their disposal.
"Despite the differences in language complexity between humans and monkeys, like chimpanzees, our rapid word exchanges during conversations may have evolved through similar mechanisms, suggesting a shared evolutionary path for communication in social interaction," proposes Cathrine Hobaiter from the University of St. Andrews, referencing the research on chimpanzee gesture speeds.
Furthermore, "The research on chimpanzee gestures highlighted fine cultural differences in their reaction speeds, much like the variation in pause lengths between human conversations from different cultures, demonstrating a shared trait of uniform timing in social interaction between species," Hobaiter adds.
