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Hub AI
Handedness AI simulator
(@Handedness_simulator)
Hub AI
Handedness AI simulator
(@Handedness_simulator)
Handedness
In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to and causing it to be 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. It is fairly common for people to prefer to do a particular task with a particular hand. Mixed-handed people change hand preference depending on the task.
Not to be confused with handedness, ambidexterity describes having equal ability in both hands. Those who learn it still tend to favor their originally dominant hand. Natural ambidexterity (equal preference of either hand) does exist, but it is rare—most people prefer using one hand for most purposes.
Most research suggests that left-handedness has an epigenetic marker—a combination of genetics, biology and the environment. In some cultures, the use of the left hand can be considered disrespectful. 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 involve 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.
Handedness may be measured behaviourally (performance measures) or through questionnaires (preference measures). The Edinburgh Handedness Inventory has been used since 1971 but contains some dated questions and is hard to score. Revisions have been published by Veale and by Williams. The longer Waterloo Handedness Questionnaire is not widely accessible. More recently, the Flinders Handedness Survey (FLANDERS) has been developed.
Handedness has been found in dozens of non-human vertebrates. While data for fish is contentious, handedness has been found in amphibians, reptiles, birds, and various mammals. Some non-human primates have a preferred hand for tasks, but they do not display a strong right-biased preference like modern humans, with individuals equally split between right-handed and left-handed preferences. When exactly a right handed preference developed in the human lineage is unknown, although it is known through various means that Neanderthals had a right-handedness bias like modern humans.[citation needed] Attempts to determine handedness of early humans by analysing the morphology of lithic artefacts have been found to be unreliable.
There are several theories of how handedness develops.
Handedness displays a complex inheritance pattern. For example, if both parents of a child are left-handed, there is a 26% chance of their child being left-handed. A large study of twins from 25,732 families by Medland et al. (2006) indicates that the heritability of handedness is roughly 24%.
Two theoretical single-gene models have been proposed to explain the patterns of inheritance of handedness, by Marian Annett of the University of Leicester, and by Chris McManus of UCL.
Handedness
In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to and causing it to be 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. It is fairly common for people to prefer to do a particular task with a particular hand. Mixed-handed people change hand preference depending on the task.
Not to be confused with handedness, ambidexterity describes having equal ability in both hands. Those who learn it still tend to favor their originally dominant hand. Natural ambidexterity (equal preference of either hand) does exist, but it is rare—most people prefer using one hand for most purposes.
Most research suggests that left-handedness has an epigenetic marker—a combination of genetics, biology and the environment. In some cultures, the use of the left hand can be considered disrespectful. 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 involve 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.
Handedness may be measured behaviourally (performance measures) or through questionnaires (preference measures). The Edinburgh Handedness Inventory has been used since 1971 but contains some dated questions and is hard to score. Revisions have been published by Veale and by Williams. The longer Waterloo Handedness Questionnaire is not widely accessible. More recently, the Flinders Handedness Survey (FLANDERS) has been developed.
Handedness has been found in dozens of non-human vertebrates. While data for fish is contentious, handedness has been found in amphibians, reptiles, birds, and various mammals. Some non-human primates have a preferred hand for tasks, but they do not display a strong right-biased preference like modern humans, with individuals equally split between right-handed and left-handed preferences. When exactly a right handed preference developed in the human lineage is unknown, although it is known through various means that Neanderthals had a right-handedness bias like modern humans.[citation needed] Attempts to determine handedness of early humans by analysing the morphology of lithic artefacts have been found to be unreliable.
There are several theories of how handedness develops.
Handedness displays a complex inheritance pattern. For example, if both parents of a child are left-handed, there is a 26% chance of their child being left-handed. A large study of twins from 25,732 families by Medland et al. (2006) indicates that the heritability of handedness is roughly 24%.
Two theoretical single-gene models have been proposed to explain the patterns of inheritance of handedness, by Marian Annett of the University of Leicester, and by Chris McManus of UCL.
