In a recent study humans ability to learn to throw at long distances unlike any other species on earth has been highlighted.
The study by Indiana University and the University of Wyoming has suggested that this unique evolutionary trait is entangled with language development in a way critical to our very existence.
The study has shown that the well-established size-weight illusion, where a person who is holding two objects of equal weight will consider the larger object to be much lighter, is more than just curious or interesting, but a necessary precursor to humans' ability to learn to throw-and to throw far.
"These days we celebrate our unique throwing abilities on the football or baseball field or basketball court, but these abilities are a large part of what made us successful as a species," said Geoffrey Bingham, IU's Department of Psychological and Brain Sciences.
"It was not just language. It was language and throwing that led to the survival of Homo sapiens, and we are now beginning to gain some understanding of how these abilities are rapidly acquired by members of our species," he said.
Bingham and Qin Zhu, lead author of the study, consider throwing and language in concert, because both require extremely well-coordinated timing and motor skills, which are facilitated by two uniquely developed brain structures-the cerebellum and posterior parietal cortex.
Bingham and Zhu put their theory to the test, recruiting 12 adult men and women to perform various tests related to perception, the size-weight illusion and throwing prowess.
Another way of stating the size-weight illusion is that for someone to perceive that two objects-one larger than the other-weigh the same, the larger object must weigh significantly more than the smaller object.
Their study findings have shown that skilled throwers use this illusion of 'equal felt' heaviness to select objects that they are able to throw to the farthest, maximum distance.
The findings appeared in the journal Evolution and Human Behavior.