The prevalence of left-handedness is a topic that has intrigued scientists for over a century. While no definitive explanation has been found, several hypotheses point to a genetic influence. The global percentage of left-handed individuals remains consistent, suggesting a genetic basis for handedness.
Some experts propose that social cooperation over thousands of years has favoured right-handedness. In communities where individuals share similar work and living space, having similar hand-functioning requirements is an advantage. Another hypothesis relates handedness to the organisation of the brain’s two hemispheres. Since the left hemisphere typically controls language and fine motor skills, this bias is thought to lead to right-handed dominance.
An unusual hypothesis suggests that a genetic mutation in the distant past shifted the brain’s language centres to the left hemisphere, promoting right-handedness. Also, though genetic makeup could be one of the reasons behind the handedness, several factors affect such an outcome. Identifying the genes responsible for handedness has proven challenging, although some progress has been made recently.
Studies have also explored the influence of factors such as estrogen levels and birth position on handedness. The complexity of the issue makes it difficult to draw a broad conclusion. Despite ongoing research, a definitive explanation for why individuals are born left, or right-handed has yet to be determined. Additionally, scientists will need to explain the phenomenon of ambidexterity, where individuals can use both hands with equal skill.
In summary, while the prevalence of left-handedness remains a puzzle, researchers are actively studying the genetic and environmental factors contributing to handedness. Through ongoing research, scientists hope to understand why some individuals are left-handed fully, others are right-handed, and some are ambidextrous.