Researchers say, because humans can interpret chimp hand gestures:
Graham’s St. Andrews colleague Catherine Hobaiter built a similar body-language dictionary by observing the East African chimpanzees at the Budongo Central Forest Reserve in Uganda. The gestures of both species, which are humans’ two closest relatives, are more complex and varied than their vocalizations, which mainly reflect urgent needs such as finding food or spotting predators.
By contrast, the apes’ gestures serve as a deliberate way of conveying specific everyday goals, leading some scientists to believe that these signals are the precursors to human language. “They are using gestures in a way that is more languagelike, and so there’s this theory that human language might have evolved from this gestural basis,” Graham says.
In a paper published today in PLOS Biology, Graham and Hobaiter provide startling evidence that this ancestral ability may persist in modern humans. They show that our species can make a pretty good guess of the meanings of chimp and bonobo gestures, another hint that language may have evolved from an elaborate system of hand and body signals.Ingrid Wickelgren, “Humans Can Correctly Guess the Meaning of Chimp Gestures” at Scientific American (January 24, 2022) The paper is open access.
No, sorry. There is lots of info out there featuring people making nice with octopuses and interpreting their gestures. But at least no one claims that human language evolved from that. It was closer to the other way around, actually…
You may also wish to read: Octopuses get emotional about pain, research suggests. The smartest of invertebrates, the octopus, once again prompts us to rethink what we believe to be the origin of intelligence. The brainy cephalopods behaved about the same as lab rats under similar conditions, raising both neuroscience and ethical issues.
You may also wish to read: But, in the end, did the chimpanzee really talk? A recent article in the Smithsonian Magazine sheds light on the motivations behind the need to see bonobos as something like an oppressed people, rather than apes in need of protection.