Why are there so few people in the world who use their left hand to do their routine work, or in other words, why are left-handed people so rare? From ear to toe, many of our organs are not the same even though they are alike, like forty percent of us can hear better with the left ear. People usually hear better with the ear they prefer to listen to phone calls. Thirty percent of people see better with the left eye and twenty percent have a stronger left leg. But there is only one person out of ten whose left hand is stronger than the right hand, that is, he is a left-handed person. So most of us use the right hand more as compared to any other creature, that is, the majority of the people in the world are right-handed.
From the point of view of evolution, more use of one hand is beneficial, for example, chimpanzees use different hands for different tasks. So where did this one-in-ten ratio come from in the evolution of human beings? The teeth of ancient Neanderthal humans indicate that they also mostly used the right hand. When Neanderthals ate meat, they would clench it tightly with their teeth and cut the meat with their overuse hand. But sometimes their teeth were scratched by mistake and these scratches reveal in which hand the knife may have been. For many years, researchers have been giving many theories as to why lefties are so few, but yet no precise scientific basis has been found for this.
Evidence indicates that genes may play a role in this, and even the fetus in the womb appears to prefer the right or the left hand. Research suggests that about one in ten fetuses are seen with the left thumb in their mouth before birth, and later in most such babies, the left hand is more likely to be used. Researchers have identified about 40 genetic variants in DNA that contribute to a person being left-handed, although this is an early stage of research. But scientists are still trying to solve this complex mystery.
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