Oda Ryo, Okuda Akari, Takeda Mia, Hiraishi Kai
Graduate School of Engineering, Nagoya Institute of Technology, Nagoya, Japan.
Department of Computer Science, Nagoya Institute of Technology, Nagoya, Japan.
Evol Psychol. 2014 Oct 23;12(5):888-900. doi: 10.1177/147470491401200503.
Men's altruism may have evolved, via female choice, as a signal of either their genetic quality or their willingness to allocate resources to offspring. The possibility that men display altruism to signal their genetic quality may be tested by examining women's preference for men's altruism across the stages of the menstrual cycle. Because women can maximize reproductive benefits by mating with men who have "good genes" on high-fertility versus low-fertility days, women should show a heightened preference for male altruism on high-fertility days compared to low-fertility days, and this heightened preference should be more apparent when women evaluate men for short-term sexual relationships than for long-term committed relationships. The possibility that men display altruism to signal their willingness to provision, as opposed to their genetic quality, may be tested by examining women's preference for men's altruism toward different recipients. More specifically, altruistic behavior toward family members may reflect a willingness to provide resources for kin and, hence, willingness to provision, whereas altruistic behavior toward strangers may function as an honest signal of genetic quality. In two samples of young women (Ns = 131 and 481), we found no differences between high- and low-fertility participants in preference for men's altruism, and women preferred men's altruism more in long-term than short-term relationships. The findings suggest that men's altruistic behavior functions as a signal of willingness to provide resources rather than genetic quality.
男性的利他行为可能是通过女性的选择进化而来的，作为他们基因质量或向后代分配资源意愿的一种信号。通过研究女性在月经周期各阶段对男性利他行为的偏好，可以检验男性表现出利他行为以表明其基因质量的可能性。由于女性在高生育期与低生育期与拥有“优质基因”的男性交配能够使生殖收益最大化，所以与低生育期相比，女性在高生育期应该对男性的利他行为表现出更高的偏好，并且当女性评估男性作为短期性关系对象而非长期伴侣时，这种更高的偏好应该会更加明显。通过研究女性对男性向不同接受者表现出的利他行为的偏好，可以检验男性表现出利他行为以表明其提供资源的意愿而非基因质量的可能性。更具体地说，对家庭成员的利他行为可能反映了为亲属提供资源的意愿，进而反映了提供资源的意愿，而对陌生人的利他行为可能是基因质量的一种诚实信号。在两组年轻女性样本（样本量分别为131人和481人）中，我们发现高生育期和低生育期的参与者在对男性利他行为的偏好上没有差异，并且女性在长期关系中比在短期关系中更偏好男性的利他行为。研究结果表明，男性的利他行为起到了表明提供资源意愿而非基因质量的信号作用。
