title: Maintenance of handedness polymorphism in humans: a frequency-dependent selection model.
abstract: Frequency-dependent selection is an important process in the maintenance of genetic variation in fitness. In humans, it has been proposed that the polymorphism of handedness is maintained by negative frequency-dependent selection, through a strategic advantage of left-handers in fighting interactions. Using simple mathematical models, we explore: (1) whether it is possible to predict the range of left-handedness frequencies observed in human populations by the frequency and the violence of fighting interactions; (2) the consequences of the sex differences in the probability of transmission of hand preference to offspring. We show that a wide range of values of the frequency of left-handers can be obtained with realistic changes of the parameters values. Our models reinforce the idea that negative frequency-dependence may have played a role in maintaining left-handedness in human populations, and provide further support for the importance of fighting interactions in the evolution of hand preference. Moreover, they suggest an explanation for the occurrence of left-handedness among women in this context, namely an indirect selective advantage through their male offspring.
authors.affiliation: Institute of Evolutionary Sciences, University of Montpellier, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Billiard
authors.forename: Charlotte
authors.initials: C
authors.lastname: Faurie
authors.forename: Michel
authors.initials: M
authors.lastname: Raymond
mesh_terms: D000374:Aggression; D005260:Female; D007839:Functional Laterality / Q000235:genetics*; D005783:Gender Identity; D005787:Gene Frequency; D005828:Genetics, Population; D006801:Humans; D008297:Male; D008957:Models, Genetic; D011110:Polymorphism, Genetic; D012641:Selection, Genetic