Snippet from the article:
Stand up straight! And do something about that hair!” Annoying? Sure. But such parental advice may have made humans what we are today. Because our upright stance, and relative lack of hair, may have enabled our human ancestors to run far and fast enough to capture their prey. So say scientists in the Journal of Human Evolution.
The idea that standing on two legs and shedding all that body hair might have helped early humans keep cool on the African savanna was first trotted out in the late 1980s. But those early models had our ancestors standing still in a gentle breeze. Scientists simply didn’t have the computational power to assess what might happen when those early humans had to up and chase down a meal.
Read the rest — Upright and Hairless Make Better Long-Distance Hunters
The above article is actually a transcript of a podcast. The published model can be found here.