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 This is Scientific American 60 Seconds Science. I'm Christine Herman. Got a minute? The ability of distinguish between sounds of varying pitch makes people capable of producing and understand speech and music. And the way we are able to process pitch has been thought to be unique to our big brain species. But now there is evidence that a tiny monkey, the common marmoset from Brazil can distinguish pitch the same way we do. That's according a study of the proceedings of the National Academy of Sciences. And years ago researchers identified a region of the marmoset brain that appear to process pitch, but they need to confirm that the animals did indeed notice changes in pitch, which presented a challenge. They had to find a way to get the animal to indicate that they had heard something. So they trained the marmosets to respond to a change in pitch with a behavior. Specifically they would lick a water spout. The researcher have been had the animals listen a series of notes with the same pitch and at random they change it up. For example, when I say ma, ma, ma, ma at some points that make the pitch a bit higher. Jones Hopkins' neroscientist Shao Xinrong read researcher of the study. The actual difference in pitch, he says, was much smaller than that, but you get the idea.  And when animal hear that change, it will lick a water spout to indicate that they hear the difference., which the miniscale monkey indeed did. Because both we and marmoset have this talent, the ability like evolved in a common ancestor long ago. This type of pitch perception may thus go back more than 40 million years ago, much earlier than previously thought. And the understand of how the brain processes pitch may eventually explain why some people have perfect pitch while others are tone death. Happy birthday to you. Happy birthday to you. Thanks for the minute for Scientific American 60 Second Science. I'm Christine Herman.