Why Only 10% Of The Worlds Population Are Left



No one has been able to definitively know the reason behind this, as there are many hypotheses that have been built for more than a century to explain this phenomenon, and the evidence points to a type of genetic influence that determines whether you are Left-handed Or right hand.

But why are we talking about genetic influence?

This is because the percentage of leftists is roughly equal anywhere on the globe.

But if you are someone who likes to play soccer regularly, you will sooner or later realize that there is asymmetry throughout the body and then you will likely prefer one foot over the other when kicking the ball.

“These asymmetries can be found in all of our bodies, from our feet to our ears, our eyes, and even in our EEG,” Hannah Fry told BBC Future.

For example, try extending one of your arms along with your gaze, then raise your thumb and look at it using one eye, then try looking at it using the other eye. The eye that shows your thumb closer to you is your strongest eye likewise, you may be tempted to answer the phone or tapping through closed doors with one ear instead of the other, as this ear is your strongest ear.


But why aren't right-handed or left-handed people born 50%?

Some experts suggest that social cooperation implemented over thousands of years has given right-handed users evolutionary dominance. In other words, when human groups work together “in terms of sharing tools and living spaces,” using the same hand as everyone else is very beneficial.


Others suggest that it is related to the way the brain is arranged in the cerebral hemispheres, where the left hemisphere controls the right side of the body while the right hemisphere controls the left side of the body.

If most people's brains use the left hemisphere to control language and fine motor skills, as most thinking takes place in the left hemisphere, this bias has resulted in the comfort in using the right hand for most of our daily activities.


And one of the most curious hypotheses is to explain the rarity of use the left hand Is that a genetic mutation in our distant past causes the language centers in the human brain to shift to the left hemisphere, causing the right-handedness to dominate most of our daily activities.

Although genetics plays a big role in determining which hand to use, it is not the complete answer, as left-handed parents have children with left-handed children but still tend to have children with higher rates in general, a preference that can be seen in the womb.


In 2019 researchers at the University of Oxford looked at the DNA of nearly 400,000 people in the United Kingdom and found that four regions of the genome are generally associated with dysarthria. Three of these regions were closely related to brain development and structure, with some researchers hoping to study the biological differences between the left. And the right can shed light on how the brain develops the disciplines of the left and right hemispheres.


But other research suggests that there may be dozens of genes that play a role in determining whether we end up writing with our left or right hand.

Moreover, other studies have linked factors such as estrogen levels and birth position to the nature of left or right-handed use.

In short, it seems that there are a lot of things that must be considered before determining the main cause of this phenomenon, and researchers face difficulty in linking all of these causes together, and this means that we cannot tell you exactly why you were born left or right, but it is clear that scientists are working hard to find A clear answer to this question.

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