The idea is not new to the fighting and violence played a role in making the passage of human ancestors walked on all fours to walking on two legs. But the new study shows the advantage of the carrier physically fight from a vertical position, two-legged posture.However, human males and their cousins the great apes – chimpanzees, gorillas and orangutans – often fight each other for territory and access to females.
Among academics, there is often resistance to the reality that human beings are a violent species. It is an inherent desire to be the most peaceful of us, he said.
If this were the whole story, I expect the same to be true for men – that men are attracted to tall women, but it turns out that women are not men are attracted to medium or even short . has said.
The other explanation is that large males among our ancestors were able to defend their resources, partners and offspring. If males can hit harder than they can hit a tall man has the advantage in a fight, because it can penetrate up to hit more targets vulnerable opponent.
Carrier predicted that animals would be a blow with their forelegs when their bodies were held in an upright position than when they were horizontal, and it would be harder to hit downwards and upwards. Although it would be ideal to test these hypotheses with four-legged animals, man should always have the advantages that led our ancestors to stand, and are more practical test subjects.
This may help explain why human ancestors began walking upright ape, and because women tend to prefer tall men.
Almost all mammals, including chimpanzees and gorillas, go on all fours when they run or cover long distances on the ground. On the other hand, all kinds of four-legged stand and use their front legs to fight. They include anteaters, lions, wolves, bears, wolverines, horses, rabbits and rodents, and many primates.
In addition, the quadrupeds are stronger pulling her legs back and forth as to push forward. This results in a powerful blow to back down when on its hind legs. These advantages, which grow directly on all fours movements, can be used more effectively by an animal that fits easily on two legs.
A study by the University of Utah shows that men hit when standing on two legs when on all fours and, when it strikes down but up, giving up, the men standing combat advantage.
In both cases, the men hit the target as hard as you could on the one hand a standing posture and on hands and knees.
Carrier is not saying that women like men who physically abuse or fighting with others. He says that women like tall men because size is a product if the evolutionary advantage held by our ancestors who began to fight standing.
A new study of the carrier was published Wednesday, May 18 Public Library of Science PLoS ONE online.
Others pointed out that the great apes often fight and threaten to beat the bipedal posture, said Carrier. My study provides a mechanistic explanation for why many species of mammals bipedally to fight.
In a world of automatic weapons and guided missiles, male physical strength has little relevance to most conflicts between people, he added. But guns were common weapons for less than 15 human generations. Maybe we should not be surprised that modern women are still attracted to physical characteristics that would predict how their friends would result in a fight.
Carrier measured the force of punches by male boxers and martial artists as a hit in four different directions: forward, sideways, up and down.
From the standpoint of the theory of sexual selection, women are attracted to powerful men, not because the males can beat them strong, but because powerful men can protect themselves and their children of other males, Carrier said.
Carrier believes that the usefulness of quadruped forelegs as weapons is a side effect of how the front legs are used to walking and running. When an animal is running with his body in a horizontal position, feet touching the ground. By raising the body to an upright posture, the animal may direct that the same force against an opponent.
The transition from four-legged two-legged posture is a critical point in human evolution, but the reason for the discrepancy is still under discussion. Darwin thought that our ancestors stood up for them to manipulate tools and weapons. Later, scientists have suggested that bipedalism evolved a number of other reasons, including bringing food, heat dissipation, operating efficiently and to reach remote branches while foraging in the trees.
The variation of the length of the fingers produced by testosterone provides a useful measure of prenatal testosterone. The study compared the length of the index with the four digits and found that those with shorter ratios are more likely to engage in risk taking. These results were then confirmed by a further measure of the relationship between the index and ring fingers.
The most popular theories about why we became bipedal locomotion are based on the benefits – increased efficiency of walking and running. However, research shows the standing position is worse for locomotion, contrary to the carrier initially thought.
A punching bag fitted with a sensor measures the force of fists forward and sideways. To strike down and bottom, the men struck a heavy block padded at the end of a lever that swung up and down because he was suspended from a axis.