"Born to Run" by Christopher McDougall was a best seller, and its
Japanese edition was published in 2010. I thought it had some relation
to hiking, so I read this book and searched the background researches.
The Born To Run hypothesis is proposed by Lieberman, et al.
You can read their theory at this site.
http://www.barefootrunning.fas.harvard.edu/index.html
Bramble, D.M.& Lieberman, D.E 2004 Endurance running and the
evolution Homo. Nature, 432, 345-352.
They asserted that the feature of human being was the higher ability
for long-distance running than other anthropoid apes. Then we lost
hair, because the physical cooling was possible by mass sweating. We
were inferior to the four legs animals such as horses at the short
interval. However, we could continue chasing an animal for hours, and
then we could kill and eat, because we had an ability of long-time
long-distance running.
However, there are several contradictory facts.
1. The energy cost of running of human being is almost double as
compared to horse's. ( Bramble, D.M.& Lieberman, D.E 2004 , P.347 )
-->The hunting by endurance running is not economical and time
consuming.
2. The molar enamel of the ancient human is thicker, and the chin is
more firm than an anthropoid ape.
---> We ate frequently very hard food. not meat.
3. Our tooth should be sharp like a lion if we ate a lot of fresh meat.
--> We must had ate something different from meat. There is a
hypothesis from dietary behavior. The ancient human may ate the left
over bones of the animal, killed by other animal. We had survived at
the niche of food, because we know how to broke bones by stone. No
animal could eat bone. So we did not need to hurry to get protein.
4. The most adequate ratio of nutrient of human may be carbohydrate
60 - 70%, protein 10 - 15%, fat 9 - 11%. If we eat more protein and
fat, life became short.
--> Our predominant food is carbohydrate. not meat.
5. We are very weak, when we are confronted to the lack of water. Our
cognition begin to deteriorate when 1.5% water of body weight was
lost. --> We evolved in water abundant environment.
6. We lose salt when we sweat. This is a very unique point.
---> We evolved in the small forest near large salt lake. ( My
little modified version of aqua hypothesis )
At first, I had deleted the section of born to run hypothesis from my
hiking handbook, but my editor rejected my manuscript, and insisted to
include them. Therefore, I explained this hypothesis in the last
chapter " Why we hike ? ". We feel comfort and enjoyment when we are
surrounded the wide natural perspective, including large lake and
forest, because we evolved in such an environment.