One of the lingering challenges in cognitive psychology is the evolution of language. Even though it's so much a part of what it means to be human.

But a new clue to language's early formation comes from chimpanzee behavior.

It's the brain's left hemisphere that controls most of our language—and a study to be published in the January 2010 issue of the journal Cortex shows that chimps have a strong preference for using their right hands when communicating. (The left hemisphere controls movement on the right side of our body.)

Researchers studied hand use in 70 chimps over 10 months. They recorded movements that displayed communications like greeting, threat, invitations, aggression or play. And found that chimps used their right hand significantly more when trying to communicate, than for other manual actions (like grooming or opening something) .

Scientists also showed that this type of gestural communication is used between chimps, and not just when they were trying to communicate with humans. Interesting to note the chimps' gestures matched some specifics of language, like intentionality to do something and making references between objects.

But perhaps even more interesting is that this study provides further support to the theory that our communication originated with gestures. Which might explain why we wave our hands, exhaustively, when trying to be understood in countries where we don't speak the language.

Now, we should see for ourselves if we gesticulate more righty than lefty.