It was never so easy to get YouTube subscribers
Get Free YouTube Subscribers, Views and Likes

Why are some people left-handed? - Daniel M. Abrams

Follow
TED-Ed

View full lesson: http://ed.ted.com/lessons/whyaresom...

Today, about onetenth of the world’s population are southpaws. Why are such a small proportion of people lefthanded and why does the trait exist in the first place? Daniel M. Abrams investigates how the uneven ratio of lefties and righties gives insight into a balance between competitive and cooperative pressures on human evolution.

Lesson by Daniel M. Abrams, animation by TEDEd.

posted by emetinav7