School of Biology, University of Nottingham, UK.
Br J Psychol. 2010 Nov;101(Pt 4):809-19. doi: 10.1348/000712610X493494. Epub 2010 Mar 23.
Altruistic behaviour raises major questions for psychology and biology. One hypothesis proposes that human altruistic behaviour evolved as a result of sexual selection. Mechanisms that seek to explain how sexual selection works suggest genetic influence acting on both the mate preference for the trait and the preferred trait itself. We used a twin study to estimate whether genetic effects influenced responses to psychometric scales measuring mate preference towards altruistic traits (MPAT) and the preferred trait (i.e., 'altruistic personality'). As predicted, we found significant genetic effects influencing variation in both. We also predicted that individuals expressing stronger MPAT and 'altruistic personality' would have mated at a greater frequency in ancestral populations. We found evidence for this in that 67% of the covariance in the phenotypic correlation between the two scales was associated with significant genetic effects. Both sets of findings are thus consistent with the hypothesized link between sexual selection and human altruism towards non-kin. We discuss how this study contributes to our understanding of altruistic behaviour and how further work might extend this understanding.
利他行为给心理学和生物学提出了重大问题。有一种假设认为，人类的利他行为是性选择的结果。试图解释性选择如何起作用的机制表明，遗传对伴侣对特质的偏好和偏好的特质本身都有影响。我们使用双胞胎研究来估计遗传是否影响了衡量对利他特质（MPAT）和偏好特质（即“利他人格”）的伴侣偏好的心理计量表的反应。正如我们所预测的那样，我们发现遗传对两者的变异都有显著的影响。我们还预测，在祖先群体中，表达更强的 MPAT 和“利他人格”的个体的交配频率会更高。我们在这方面找到了证据，即两个量表之间表型相关的协方差的 67%与显著的遗传效应有关。这两组发现都与性选择和人类对非亲属的利他行为之间的假设联系相一致。我们讨论了这项研究如何有助于我们理解利他行为，以及进一步的工作如何扩展这种理解。
