In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to it being stronger, faster or more dextrous. The other hand, comparatively often the weaker, less dextrous or simply less subjectively preferred, is called the non-dominant hand.
In a study from 1975 on 7,688 children in US grades 1-6, left handers comprised 9.6% of the sample, with 10.5% of male children and 8.7% of female children being left-handed.
Overall, around 90% of people are right-handed. Handedness is often defined by one's writing hand, as it is fairly common for people to prefer to do a particular task with a particular hand. There are people with true ambidexterity (equal preference of either hand), but it is rare - most people prefer using one hand for most purposes.
Most of the current research suggests that left-handedness has an epigenetic marker - a combination of genetics, biology and the environment.
Because the vast majority of the population is right-handed, many devices are designed for use by right-handed people, making their use by left-handed people more difficult.
In many countries, left-handed people are or were required to write with their right hands. However, left-handed people have an advantage in sports that involves aiming at a target in an area of an opponent's control, as their opponents are more accustomed to the right-handed majority. As a result, they are over-represented in baseball, tennis, fencing, cricket, boxing, and mixed martial arts. Continue reading
A Shape Called a 'Sphinx' Could Explain Handedness in Biology Science Alert - March 31, 2024
From the helix of a strand of DNA to the arrangements of protein's building blocks, the twists and swirls of biochemistry often follow a surprisingly consistent orientation of left- and right-handedness known as chirality. A recent study involving the tesselations of a simple shape based on triangles might help us better understand why biology holds preferences for one orientation over the other. Conducted by a small team of researchers from the US and Germany, the investigation shows how a combination of geometry and basic physics might be behind some of life's most intriguing patterns.