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Assessing Differences in Sperm Competitive Ability in Drosophila
Published on: August 22, 2013
Comparative reproductive output of androphilic and gynephilic males in samoa
Paul L Vasey1, Jessica L Parker, Doug P VanderLaan
1Department of Psychology, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada, paul.vasey@uleth.ca.
Abstract:
Debate exists in the behavioral sciences regarding the extent to which androphilic males reproduce compared to their gynephilic counterparts. Quantitative data that might speak to this debate are surprisingly rare. Here, we compared the reproductive output of 235 transgendered, exclusively androphilic Samoan males (known locally as fa'afafine) to that of 447 exclusively gynephilic Samoan males. Samoan gynephilic male participants fathered significantly more children than fa'afafine participants. In fact, none of the fa'afafine in our sample produced offspring. On the basis of this evidence and anecdotal accounts in the anthropological literature, we contend that absence of reproductive output is a near absolute cross-cultural universal characterizing non-Western, transgendered androphilic ("third-gender") males. Models for the evolution of male androphilia must account for how genes associated with this sexual orientation originated in the past and persisted in populations over time despite the fact that the vast majority of androphilic males have no direct reproductive success.
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