Do you motion with your hands when you talk? Most people do. The movements come naturally to us, and often happen without any conscious planning. We speak, and our hands get into the act.
Undoubtedly, a lot of this behavior is learned. If you raise a child in Italy, she’ll grow up learning different gestures than if you raise her in Japan, Nigeria, or Canada. She’ll also learn different social norms about the desirability of gesturing. By the age of two years, Italian children produce about twice as many communicative gestures as do English-speaking Canadian kids (Marentette et al 2016).
But cultural variation doesn’t change the fact that gesturing is a species-typical behavior. Like speech, music, or dance, gesture is part of our biological heritage. Children who are blind from birth use gestures when they talk, even when speaking to other sightless people (Iverson and Goldin-Meadow 1998). And fieldwork on the great apes suggests that our ancestors used their hands to communicate long before the evolution of speech (deWaal and Pollick 2006; Byrne et al 2017).
Why do we do it nowadays? Is it mere hand-waving? Is it a useless atavism, an evolutionary leftover that serves no modern purpose? Research suggest otherwise.
As it turns out, our hand movements have a substantial impact on the way we learn, reason, and solve problems
Babies exposed to lots of communicative gestures appear to learn language more quickly, and acquire bigger vocabularies. It’s helpful to have a parent who is a good gesturer.
Young children also seem to benefit from making gestures. For instance, toddlers who point are more likely to elicit helpful information from adults (“Oh! That’s a dog!”), which may explain why these children develop larger vocabularies over time.
Experiments indicate that gesturing helps students master new mathematical concepts, reason about spatial relationships, and solve logical puzzles.
With all this evidence, we really should be in the business of encouraging gesture, at least the kind that boosts communication and intellectual performance. Far from being outmoded or redundant, gesture plays an important role in cognitive development and problem-solving. Here are the details.