Scientists have discovered that wild chimpanzees use at least 66 different gestures to communicate with each other.
The researchers from St Andrews University in Scotland studied chimps in Budongo Conservation Field Station, Uganda. They analysed 120 hours of footage of the chimps interacting, looking for clear signs that the animals were making deliberate movements that were intended to generate a response from another animal.
"We looked to see if the gesturer was looking at their audience," Professor Richard Byrne explained. "And we looked for persistence; if their action did not produce a result, they would repeat it." This article includes a short clip showing an example of the gestures identified.
The team is still studying the footage for the next stage of their project - to figure out what each gesture means. For some of these gestures, the meaning seems obvious to us, perhaps because, as great apes, we make similar movements. For example, a chimp will often beckon to another group member, or a youngster will hand shake at another juvenile to entice it to play.
This study also shows the benefits of studying animals in the wild as opposed to captivity as previous studies on captive chimps had suggested the animals have only about 30 different gestures. Lead researcher Dr Catherine Hobaiter said: "We think people previously were only seeing fractions of this, because when you study the animals in captivity you don't see all their behaviour. You wouldn't see them hunting for monkeys, taking females away on 'courtships', or encountering neighbouring groups of chimpanzees."
Clearly chimpanzee communication is even more complex than previously thought. It may well be that, like us, chimps actually use significantly more gestures that the identified 66, including subtle ones that the researchers are yet to identify.
By comparing the chimps' gestures with those made by gorillas and orangutans, the researchers showed there was significant overlap in the signals used throughout the family of great apes. According to Dr Hobaiter: “This supports our belief that the gestures that apes use (and maybe some human gestures too) are derived from ancient shared ancestry of all the great ape species alive today." After all, in times long gone by we really were all OneKind!