Monday, May 09, 2011
Humans evolved to be persistence hunters
An interesting article about how humans evolved to be runners is found here. Anthropologists have recently started coming to the conclusion that humans relied on persistence hunting in ancient times.
Persistence hunting is just what it sounds like. A human runs down a prey animal on foot over an incredibly far distance in the middle of a hot day, only catching the animal when the prey is too heat exhausted to run any more. Humans can pull this off because we run on two legs, which is more efficient over long distances. We stand upright, and so expose less surface area to the sun. The sun only touches the top of our head and shoulders; in prey animals, the whole back is exposed.
Humans also have no hair, and have sweat glands over our entire body. Both of these things allow us to efficiently cool ourselves even in the hottest weather. In fact, military experiments demonstrated that humans can withstand 400 degree heat for an hour easily IF they have enough water and the air is dry - that is how efficient our sweating is. In the prehistoric human, intelligence allowed the use of containers to carry water on these persistence hunts. Empty ostrich eggs were the Nalgene bottles of 100,000 years ago.
I had read about persistence hunting before going to Africa. When we were driving through Kenya, and I felt the intense heat and appreciated the lack of water, I thought to myself "oh, that makes sense." You see, the Kenyan sun and heat isn't a liability for the humans - its an advantage. The dry hot weather and lack of water exposes the vulnerability of the prey animals: they can't cool themselves in such weather as well as humans can. In a temperate or wet climate, persistence hunting would never work.
Still not convinced that persistence hunting can work? Check out you tube video. Humans still persistence hunt today. Wouldn't that be a fun thing to do. Screw training for a marathon. I'm going to train for a persistence hunt.