Department of Economics, LoyolaBehLAB, Universidad Loyola Andalucía, Cordoba, Andalucia 14004, Spain.
Department of Social Anthropology, Universidad de Granada, Granada, Granada 18071, Spain.
Biol Lett. 2019 Aug 30;15(8):20190185. doi: 10.1098/rsbl.2019.0185. Epub 2019 Aug 28.
Prenatal exposure to sex hormones exerts organizational effects on the brain which have observable behavioural correlates in adult life. There are reasons to expect that social behaviours-fundamental for the evolutionary success of humans-might be related to biological factors such as prenatal sex hormone exposure. Nevertheless, the existing literature is inconclusive as to whether and how prenatal exposure to testosterone and oestrogen, proxied by the second-to-fourth digit ratio (2D : 4D), may predict non-selfish behaviour. Here, we investigate this question using economic experiments with real monetary stakes and analyse five different dimensions of social behaviour in a comparatively large sample of Caucasian participants (n = 560). For both males and females, our results show no robust association between right- or left-hand 2D : 4D and generosity, bargaining or trust-related behaviours. Moreover, no differences in behaviour were found according to sex. We conclude that there is no direct correlation between 2D : 4D and these social behaviours.
产前暴露于性激素会对大脑产生组织效应，这些效应在成年后具有可观察到的行为相关性。有理由预期，对于人类的进化成功至关重要的社会行为可能与生物因素有关，例如产前性激素暴露。然而，现有文献对于产前暴露于睾丸素和雌激素（通过第二到第四指比率（2D：4D）来代理）是否以及如何可以预测非自私行为尚无定论。在这里，我们使用具有实际货币赌注的经济实验来研究这个问题，并在一个相对较大的白种人参与者样本（n = 560）中分析了社会行为的五个不同维度。对于男性和女性，我们的结果均显示右手或左手 2D：4D 与慷慨，讨价还价或与信任相关的行为之间没有牢固的关联。此外，根据性别没有发现行为上的差异。我们的结论是，2D：4D 与这些社会行为之间没有直接的相关性。
