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Updated: Jul 28, 2026
07:54
Design, Fabrication, and Administration of the Hand Active Sensation Test (HASTe)
Published on: September 8, 2015
Handedness, homicide and negative frequency-dependent selection
Charlotte Faurie1, Michel Raymond
1Genetics of Adaptation, Institute of Evolutionary Sciences (UMR CNRS 5554), University Montpellier II, CC 065, 34095 Montpellier 5, France. faurie@isem.univ-montp2.fr
Proceedings. Biological Sciences
|May 7, 2005
Summary
Left-handedness, though rare, may offer a survival advantage in violent societies. Higher homicide rates correlate with increased left-hand prevalence, suggesting a frequency-dependent selection mechanism.
Area of Science:
- Evolutionary biology
- Human evolution
- Behavioral genetics
Background:
- Hand preference, or handedness, is a heritable trait with left-handers being a minority across human populations.
- The persistence of left-handedness despite potential fitness costs suggests a balancing selection mechanism.
- Previous research indicated a potential frequency-dependent advantage for left-handers in competitive interactions like fights.
Purpose of the Study:
- To investigate the relationship between handedness prevalence and societal violence.
- To test the hypothesis that left-handedness confers a frequency-dependent advantage in conflict-prone societies.
Main Methods:
- Cross-cultural analysis correlating the frequency of left-handers with homicide rates in traditional societies.
- Utilizing existing anthropological and sociological data on societal violence and handedness.
Main Results:
- A strong positive correlation was found between the prevalence of left-handedness and homicide rates across diverse societies.
- Left-handedness frequency ranged from 3% in pacifistic societies to 27% in highly warlike societies.
- This observed pattern supports the frequency-dependent selection hypothesis for maintaining left-handedness.
Conclusions:
- Left-handedness may be maintained in the human population due to a frequency-dependent advantage in violent contexts.
- Societal violence levels appear to be a significant factor influencing the prevalence of left-handedness.
- The study provides evolutionary insights into the persistence of handedness polymorphism.
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