Southpaws thrash righties: study
Researchers have suggested that left-handed people are better at surviving fights to the death.
Charlotte Faurie and Michel Raymond of the University of Montpellier in France found that the greater the homicide rate in unindustrialised cultures, the higher the proportion of left handed people. Industrialised cultures were excluded from the survey due to a lack of data and, according to the researchers, because some weapons, such as guns, used in such societies would provide no advantage for either left or right handed people.
Among the Dioula of Burkina Faso, the homicide rate is 0.013 per 1,000 and 3.4 per cent of the population is left-handed. However, among the Eipo of Indonesia, there are three murders for every 1,000 people and 27 per cent are left handed. Faurie and Raymond suggested that the cause for this is that left-handers are more likely to survive hand-to-hand combat.
Left handed competitors tend to do better than right handed ones in sports such as tennis. It is thought that this is because right-handed people are not used to facing lefties because there are fewer of them, while left-handed people play against righties most of the time. "Because of the advantage in sports we thought there could be a similar advantage in fights," Faurie told New Scientist.
In many cultures, winning a lot of fights will enhance your status and, the theory is, in prehistory this may have increased your reproductive success, thereby explaining the greater number of left-handed people in more violent societies.
However, some scientists are unconvinced that there is a link. Chris McManus at University College London, who has researched handedness, said, "I don't think it is anything as simple as this."
He says that the sample data used is too limited to provide evidence of a link between handedness and fighting ability, and that data from industrialised cultures should have been included.
He believes that left handed people may have an advantage due to their brains being structured differently. "It may be that sometimes their brains assemble themselves in combinations that work better for certain tasks," he says.
Left handed people are more likely to have certain health problems, including immune disorders, and thus logically the trait should have been removed by natural selection. The fact that there are still lefties in the population either suggests that being left-handed provides some survival advantage, or is a product of left-handedness not being governed by simple inheritance principles. For instance, there is only a 76 per cent chance that indentical twins, who have identical genes, will both use the same writing hand.
It is not known at this time whether being ambidexterous offers a significant advantage in combat. ®