Ancient human ancestors often needed to climb trees to gather food and other necessary supplies, and up until recently, tree climbing was the only explanation for their extremely short legs.
However, David Carrier, a biology professor at the U, believes there is another explanation for short legs-they make better fighters.
Carrier began his study after two male dogs he adopted sparked his interest in leg length and aggression.
“The two dogs were always fighting,” Carrier said. “I attempted to break up the fights for a couple of weeks, but after a while I gave up and began just watching them fight.”
Carrier noticed that the faster dog with longer legs would start all the fights but the shorter, slower dog always won.
“I couldn’t help but make a comparison to early human ancestors-Australopithecus,” Carrier said. “I was interested to see if leg length and aggression were related.”
These ancient ancestors were similar to modern-day great apes (such as gorillas, chimpanzees and orangutans) in that they were constantly fighting for access to females.
Carrier looked at fossils of Australopithecus and modern-day great apes and said that the skeletons were very similar. Both had short legs and a relatively long torso.
“You are more stable if you lower your center of gravity,” Carrier said. “It takes more force to knock something with a short, broad stance, and being short lets you use the ground for leverage.”
Since humans’ close relatives are aggressive, it would make sense that humans are aggressive, as well, he said.
“It would be interesting to see if short legs in relations to aggression holds true for humans,” Carrier said.
Since Carrier can’t directly study aggression in most humans, he hopes to turn to wrestlers and boxers.
Carrier said, “I want to compare leg length of Olympic boxers and wrestlers to that of the general population and see if the pattern is consistent.”