Born to Run

Does having a big butt help you run? According to University of Utah biologist Dennis Bramble and Harvard University anthropologist Daniel Lieberman it does! Featured in the November 18th issue of the scientific journal, Nature, Bramble and Lieberman discussed the theory that the human anatomy evolved the way it did because of the need to cover long distances and compete for food.

Bramble and Lieberman argue that our genus, Homo, evolved from more ape-like human ancestors 2 million or more years ago because natural selection favored the survival of a species that could run and, over time, favored the perpetuation of human anatomical features that made long-distance running possible.

“Running has substantially shaped human evolution. Running made us human — at least in an anatomical sense,” Bramble continues, “We think running is one of the most transforming events in human history. We are arguing the emergence of humans is tied to the evolution of running.”

From tendons and ligaments in the legs and feet that act like springs and skull features that help prevent overheating to a well-defined buttocks that stabilizes the body, humans were made to run.

So why has the scientific community dismissed running as a factor in human evolution in the past? The answer may lie in the fact that humans are poor sprinters compared to other running animals. Human endurance running ability has been underappreciated because of the failure to recognize that “high speed is not always important,” Bramble says. “What is important is combining reasonable speed with exceptional endurance.”

As endurance athletes we can appreciate our body’s ability to run well. Lieberman stated that “we do it because we are good at it. We enjoy it and we have all kinds of specializations that permit us to run well.”

Some uniquely human running characteristics include:

• Larger surface areas in the hip, knee, and ankle joints improve shock absorption.
• Shorter forearms make it easier for the upper body to counterbalance the lower body during running.
• A more balanced head with a flatter face, smaller teeth, and short snout shifts the center of mass back, easier enabling you to balance your head while it’s bobbing up and down while running.
• The arrangement of bones in the human foot creates a stable or stiff arch that makes the foot more rigid which allows the foot to push off the ground more efficiently.
• Human buttocks are huge compared to animals such as apes. These muscles are critical for stabilization, because they connect the femur to the trunk.

This is an article I wrote last fall for a writing class. I thought it was super interesting since we have been stuck in the humans-are-the-way-they-are-because-we-learned-to-walk paradigm for all of history. The idea that human anatomy and physiology developed because of our need to cover long distances is pretty cool. We were born to run; our body's allow us to be good at it.