Researchers have found that the body of men in the course of evolution has changed to more effectively fight rivals. The scientists presented their findings in an article published in the Journal of Experimental Biology.
As you know, the strongest wins the fight. And fights have continuously pursued representatives of all animal species throughout their evolutionary history. In the course of natural selection, the individuals best adapted to constant battles survived. According to the new work of scientists from the University of Utah, man did not escape this fate.
For several years, researchers have hypothesized that generations of interpersonal aggression between men in the distant past formed structures in human bodies specialized for fighting. Past work has shown that the shape and proportions of men's hands allow not only to increase their dexterity, but also to protect them when hitting with a fist. Other studies have looked at the strength of the bones of the face (as a likely target for impact) and how our heels can add extra strength to the upper body.
The authors of the new work suggested that if men in battles tend to do punches with their hands, then in the course of evolution they should have formed stronger muscles associated with this action. Early research showed that men have an average of 75% more mass and 90% more strength in men than women. But why and how it happened so far remained unclear.
To find out, scientists have developed a special experiment. They decided to test the force of the blows of the men. But not with the help of a pear - it is quite traumatic. Instead, the researchers constructed a grip that mimicked movement when struck. The authors also measured the strength of the participants in a javelin-like action to test an alternative hypothesis that the strength of the upper body in males could be developed for hunting.
Researcher-created setup
The study involved 20 men and 19 women. They were selected after completing a special questionnaire on daily physical activity. It turned out that even at approximately the same level of physical fitness, the average strength of men during percussion movements was 162% greater than that of women, with the least strong man still stronger than the strongest woman. Such sexual dimorphism, according to the findings of scientists, develops over time and with a specific purpose. Researchers believe that the reason for this is the need for men to participate in fights.