Why are there more right-handers than left-handers?

In this article we will analyze the fight hypothesis that talks about left-handedness, fight and survival, and we will turn to the most recent empirical evidence that explains Why are there more right-handers than left-handers? according to an interesting line of research.

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Left-handed, right-handed and ambidextrous

Left-handed people are those who tend to preferentially use the left side of their body (that is, their hands and feet).

Left-handedness is a minority phenotype in the human species.; that is, there are more right-handed people (who prefer to use their right limbs) than left-handed people.

In fact, between 8 and 13% of the world population is left-handed; On the other hand, there are more left-handed men than left-handed women (13% vs. 9%), although it is not known why. Finally, it is worth mentioning that those people who use the right and left extremities interchangeably are called ambidextrous.

Why there are more right-handers than left-handers, according to research

As we anticipated in the introduction, this article focuses on the fact that there are many more people who have their right hand as their dominant hand. Why are there more right-handers than left-handers? But before delving into this question, we are going to clarify why there are left-handed people in the population, according to the fight hypothesis.

According to this hypothesis, there are lefties in the population because in the past, left-handed people had an advantage in violent intrasexual type competitions. This, according to this hypothesis, would explain why left-handedness persisted over time.

fight hypothesis

But what does the wrestling hypothesis specifically say about left-handedness?

According to this hypothesis, there is a polymorphism (polymorphism implies the existence, in a population, of multiple alleles of a gene) in human hands, which is maintained over time by a process of natural selection; in the case of left-handed people, this process is a frequency-dependent selection.

What does this mean? That when a trait offers a certain biological efficacy to a certain species (increasing its probability of survival), said trait remains, even in the event that it is a minority (as would be the left-handed).

How does this extrapolate to the field of wrestling and left-handedness? Right-handed fighters are used to fighting other right-handed fighters; for this reason, when they compete against a left-handed fighter, the latter will have a certain advantage in the fight (and therefore, surely he will have greater probability of winning), since the left-handed wrestler is more used to fighting against a right-handed than the right-handed against a left handed.

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Empirical evidence: study

We found different studies that show how left-handed men are overrepresented among modern professional wrestlers. A recent study (2019) by Richardson and Gilman, also raised the question of why there are more right-handers than left-handers and focused on the world of boxing and wrestling.

Sample

This study analyzed a total of 13,800 boxers and fighters of different martial arts, mixed type.

That is, the sample included men and women. However, it is worth mentioning that of the total number of boxers, 10,445 were men (8,666 right-handed and 1,779 left-handed), 1,314 were women (1,150 right-handed and 164 left-handed) and 2,100 were MMA (mixed martial arts) fighters (1,770 right-handed and 393 left-handed).

Through these data we see how left-handed men represent 12.6% of the general population, 17% of men within the world of boxing, and 18.7% in the MMA sector; in the case of women, they represent 9.9% of the general population, and 12.5% ​​of female boxers. We see how, in both cases, left-handedness is overrepresented in the wrestling world.

Study objectives

The study intended to verify two aspects; on the one hand, whether or not there is an overrepresentation of left-handed wrestlers compared to right-handed ones, and on the other, if they accumulate more victories than right-handed ones.

Results

The results of the Richardson and Gilman study revealed that, indeed, left-handed boxers and wrestlers had more wins (number of fights won) than right-handed ones. This was reflected in both male wrestlers and female wrestlers..

In addition, the fighting capacity of the wrestlers and wrestlers was also evaluated, through an objective measure, and the results were in the same line; left-handers had a better fighting ability than right-handed ones.

Another hypothesis that was raised and analyzed in the aforementioned study is another already suggested by previous studies, and it was the following: the fact that left-handed fighters show a greater variation in combat ability. Said hypothesis could not be confirmed, since said variation was not observed in left-handed wrestlers.

conclusions

As we have seen, analyzing the question of why there are more right-handers than left-handers, we come to the following conclusion: the fact that left-handers are a minority (which is why they are overrepresented), makes his actions and techniques harder for his rivals to predict.

This can be explained by the tendency of right-handed opponents to attend mainly to the right hand of their opponent (this is a bias attentional), and this tendency would appear because right-handers would be accustomed (generally competing with right-handed rivals) to attend to said hand.

Hypothesis verification

Thus, what is currently happening in the field of wrestling and boxing can be extrapolated to our ancestors; this way, it is likely that our left-handed ancestors, as the wrestling hypothesis suggests, had some advantage in violent combats (being these, moreover, more frequent in the past than at present), which gave them a certain evolutionary advantage.

In this way, we see how the hypothesis of the fight would be fulfilled, since the fact of being left-handed or left-handed implies an advantage in this type of sports.

Bibliographic references:

• Bejarano, M. TO. & Naranjo, J. (2014) Laterality and sports performance. Arch Med Sport, 31(3), 200-204.
• Hardyck, C., & Petrinovich, L. F. (1977). Left-handedness, Psychological Bulletin, 84, 385–404.
• Richardson, T. & Gilman, R.T. (2019). Left-handedness is associated with greater fighting success in humans. Sci Rep 9, 15402.