Female counter-strategies to male infanticide in primates

灵长类生活在群体中，两性之间的社会关系表现出很大的差异。这些关系受到雄性生殖竞争和雌性择偶的影响。男性有时会利用男性对女性的性胁迫来获得交配机会，男性性胁迫的一个极端表现是男性杀人。杀婴的雄性如果杀死不相关的婴儿，那么它们会使雌性更快地受精，而不是等到断奶。在许多灵长类动物中都观察到了雄性杀精现象，但现在很明显，并非所有容易被杀精的个体都会被杀死。这表明，并非所有的男性都是杀精的，和/或存在成功的男性和女性的反策略，以男性杀精。杀婴对于生下受害者的雄性来说代价高昂，但对于雌性哺乳动物来说代价更高，因为它们的潜在生殖输出更有限。因此，自然选择应该有利于女性反策略的表达。我将调查女性行为的表达，可能有资格作为反策略，以杀婴，在杀婴风险的情况下，这些女性的经验各不相同。居民男性的亲子关系确定性水平与其群体中母亲经历的死亡风险水平呈负相关。在我们研究的灵长类动物中，杀婴率很高，但杀婴的风险并不是在所有社会条件下均匀分布的。生活在单一男性群体中的女性面临的死亡风险最小，因为这些群体中的男性有很高的亲子关系确定性。生活在稳定的多男性群体中的女性面临着中等程度的杀婴威胁，因为这些群体中的男性个体比单一男性群体中的男性个体具有更低的亲子关系确定性。在刚被接管后，被杀的风险是最严重的，因为新来的雄性几乎没有亲子关系。 我将研究是否有资格作为反策略的行为表达对杀螨剂（与男性保护者，增加性接受能力，与多个男性交配，快速断奶）与杀螨剂的风险水平共变，如果他们影响婴儿存活率和女性生殖成功。

Primates live in groups that show great variation in social relationships between the sexes. These relationships are influenced by male reproductive competition and female mate choice. Males sometimes use male sexual coercion of females to attain mating opportunities, and one extreme expression of male sexual coercion is infanticide by males. Infanticidal males benefit reproductively if they kill unrelated infants and they inseminate a female sooner than if they had to wait until weaning. Male infanticide has been observed in a wide range of primates, but it is now apparent that not all individuals vulnerable to infanticide are killed. This suggests that not all males are infanticidal, and/or the existence of successful male and female counter-strategies to male infanticide. Infanticide is costly for the males who sired the victims, but is even more costly for female mammals, that are more limited in their potential reproductive output. One should thus expect natural selection to favor the expression of female counter-strategies to infanticide. I will investigate the expression of female behaviors that could qualify as counter-strategies to infanticide, in situations where the infanticide risk that these females experience varies. The level of paternity certainty that resident male(s) have is inversely related to the level of infanticide risk experienced by the mothers in their group. Infanticide rate is high is the population of primates that we study, but the risk of infanticide is not distributed equally across all social conditions. Females living in uni-male groups face the least infanticide risk, as males in these groups have high paternity certainty. Females living in stable multi-male groups face a moderate level of infanticide threat, as individual males in these groups have lower paternity certainty than in uni-male groups. The risk of infanticide is most acute immediately after a takeover, as the newly-arrived males have a close-to-zero paternity certainty. I will examine if the expression of behaviors that qualify as counter-strategies against infanticide (association with a male protector, increased sexual receptivity, mating with multiple males, and rapid weaning) co-vary with the level of infanticide risk, and if they influence infant survival and female reproductive success.