How did evolution transform us into endurance runners

running masai

We can’t run very fast, as compared to other mammals, but we can, instead, run for a very long time. People are one of the most resistant runners in the world. Our skeleton, backbone, foot, skeletal, muscular and respiratory systems, as well as our aerobic metabolism have evolved in such a way as to allow us to run tens of kilometers without having to make a break.

Our first ancestors who have gained this ability have acquired a huge advantage both in hunting and in competition against their less resistant peers. Herbivorous animals were simply chased until total exhaustion; they ran until they would collapse, powerless, and the hunters would approach and deal the final blow.

We can still see nowadays examples of hunting by means of exhaustion. Men from some African tribes go hunting in the afternoon and attack a group of antelopes, which they can chase for up to 40-50 kilometers, for four or five hours without any break, until they (the antelopes) get exhausted and fall powerless in front of the hunters.

In prehistoric times, before the apparition of dogs and throwing weapons, the hunting was usually deployed in such a manner, and the natural selection has favored the men who were more resistant at running; they became successful hunters or warriors, they gained a high hierarchical status and were enjoying attention from women. This way nature has turned us into endurance runners.

A correlation between resistance to prolonged physical effort and a high level of testosterone în human body has strenghten. Even today, according to most recent studies, our long-distance running performance (like 21 km long semimarathons) is being proven by men who were exposed to significant level of testosterone while they were still in thir mother’s womb [Longman et al., 2015].

However, the “evolutionary logic” of appearance of bipedal locomotion in humans is still not clear, because bipedal locomotion, together with well-known advantages, have come with a number of disadvantages like the physiological state of the body, difficult gestation, problems with the backbone, slow movement etc.

According to a hypothesis proposed by the biologists from The University of Utah (US), the bipedal position has evolved as a necessary answer to the need of acquiring fighting skills. More exactly, biologists claim that the bipedal position is more advantageous during melee combat, because it allows one to strike harder, to use weapons and it grants a better visualization of one’s surroundings, in order to detect enemies.

fight bipedal

During an experiment that was carried out to test the hypothesis, it has been found out that the hits that were applied from a bipedal stance were 50-60% more powerful than those carried out from a quadrupedal position, and the hits from a higher position to a lower point were 3.3 times more powerful than those from a lower position to a higher point (due to a greater involvement of back muscles) [Carrier, 2011].

In other words, bipedal position enhances physical performance and has benefited fighters during their fighting for survival. As a consequence, the genes that favored the transmission of these anatomical characteristics have spread within the population.

© Dorian Furtună, ethologist

Sources:

Carrier D.R. The Advantage of Standing Up to Fight and the Evolution of Habitual Bipedalism in Hominins // PLoS ONE 6(5). Epub 2011 May 18. doi:10.1371/journal.pone.0019630

Longman D., Wells J.C.K., Stock J.T. Can Persistence Hunting Signal Male Quality? A Test Considering Digit Ratio in Endurance Athletes // PLOS ONE. Vol. 10 (4). 2015. e0121560. DOI: 10.1371/journal.pone.0121560

Photo:

Masai warriors / http://www.dailymail.co.uk/news/article-553756/Wear-pants-dont-pee-public-dont-herd-cows–Masai-marathon-runners-guide-miserable-Britain.html

Combatives demonstration – US Army Africa / by Edward N. Johnson / https://www.flickr.com/photos/usarmyafrica/4605124417/

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