The results: The longer the yawn, the bigger the brain tended to be. The strongest correlation was between yawn duration and brain complexity, as judged by the number of neurons. “What really separates humans from other animals in terms of our cognitive abilities is our neuron numbers, rather that just brain size,” Gallup said. The study authors emphasized that neither body size nor jaw size was correlated with yawn duration. He’s already in the process of exploring whether yawn duration correlates with brain size and cognitive ability in human subjects.

Source: Los Angeles Times October 06, 2016 09:56 UTC