担当：shixiang QIN
日時：5/26(木) 15:30-
場所：コラボレーションルーム2
内容：同性愛の「ダーウィンのパラドックス」についての論文紹介

論文：Genetic factors predisposing to homosexuality may increase mating
success in heterosexuals

Abstract:
There is considerable evidence that human sexual orientation is genetically
influenced, so it is not known how homosexuality, which tends
to lower reproductive success, is maintained in the population at a
relatively high frequency. One hypothesis proposes that while genes
predisposing to homosexuality reduce homosexuals' reproductive success, they
may confer some advantage in heterosexuals who carry them.
However, it is not clear what such an advantage may be. To investigate this,
we examine a data set where a large community-based twin
sample (N=4904) anonymously completed a detailed questionnaire examining
sexual behaviors and attitudes. We show that psychologically
masculine females and feminine men are (a) more likely to be nonheterosexual
but (b), when heterosexual, have more opposite-sex sexual
partners. With statistical modelling of the twin data, we show that both
these relationships are partly due to pleiotropic genetic influences
common to each trait. We also find a trend for heterosexuals with a
nonheterosexual twin to have more opposite-sex partners than do
heterosexual twin pairs. Taken together, these results suggest that genes
predisposing to homosexuality may confer a mating advantage in
heterosexuals, which could help explain the evolution and maintenance of
homosexuality in the population.

論文のダウンロードはこちらから：
http://www.matthewckeller.com/Zietsch_HomosexualityEvolution_2008.pdf