Even before birth and throughout life all animals yawn. But scientists are still unclear about why. Robert Provine, a neuroscientist at the University of Maryland in Baltimore, has studied yawning for over 30 years.
Why do we yawn?
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Even before birth and throughout life all animals yawn. But scientists are still unclear about why. Robert Provine, a neuroscientist at the University of Maryland in Baltimore, has studied yawning for over 30 years. |
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