Why are some people left-handed?
You must have seen people who eat, write or play tennis with their left hand. But more people on the earth are right-handed. Less than one person in six is left-handed.
Our brain is a complicated organ. The right half of the brain controls the left side of the body, and the left side controls the right side of the body. In most people, the left side of the brain is better developed, so the right hand is more efficient and stronger than the left one.
No one knows for sure why it happens, but sometimes in some people the right side of the brain is better developed. And this makes their left hand work better.
According to some experts, it is possible that the reason goes back to ancient days or even the days of the caveman. When people fought, a right-handed person would fight with a weapon in his right hand and use his left hand to shield his body. The left-handed person would shield himself with the right hand while using the left hand for fighting. The person who shielded his body on left side protected his heart because the heart lies on the left side. So such fighters had better chances of survival. The left handed fighters would be wounded around their heart and die. So more right-handed persons lived on earth.