Drivers and consequences of male care for young in a promiscuous primate

进化模型和经验证据预测，男性对幼崽的照顾将仅限于具有高度亲子关系确定性的物种，即夫妻结合或一夫一妻制物种，因为在这些情况下，照顾雄性的费用会减少。因此，大多数关于男性照顾进化的研究集中在成对生活和一夫一妻制的物种上。然而，自然选择将有利于男性护理的进化，即使在特定情况下亲子关系确定性较低的混杂制度中也是如此。如果当雌性根据雄性的照顾倾向选择配偶时，有爱心的雄性享受交配利益，则可以选择雄性照顾，如果它是通过吸引配偶而进行的交配努力，或者如果雄性将照顾引导到他们的遗传后代中，并且雄性照顾提高了后代的质量和健康，则可以选择雄性照顾。在拟议的项目中，我们将在非人类灵长类的混杂物种中(1)测试雄性通过交配努力和交配吸引或通过真正的父亲照顾相关幼崽获得的交配和生殖成功增加方面的好处。接下来，我们将(2)调查男性养育和交配努力之间的潜在权衡，以及潜在的策略转换，因为这两种努力的相对回报可能会在男性的一生中或随着地位的变化而变化。最后，我们将(3)通过评估在男女混杂的系统中照顾后代的适合性结果，关键地增加对男性照顾的研究。我们通过利用大量关于男性护理和性行为的长期数据集、照顾幼崽的短期和长期利益(例如成熟年龄、存活)以及自2006年以来收集的关于亲缘关系的遗传数据来解决这些目标，这些数据来自于我们的研究种群，这些种群生活在泰国东北部的自然栖息地，以混杂交配系统为特征，亲子鉴定水平较低。

Evolutionary modelling and empirical evidence predict male care for young to be restricted to species with a high degree of paternity certainty, i.e. pair-bonded or monogamous species, as costs of care for males are alleviated in these situations. Consequently, the majority of studies on the evolution of male care focused on pair-living and monogamously mating species. Natural selection, however, will favour the evolution of male care even in promiscuous systems with low paternity certainty under specific circumstances. Male care may be selected if it functions as mating effort via mate attraction if caring males enjoy mating benefits when females base their mate choice on a male’s propensity to care, or as parenting effort if males channel care into their genetic progeny and male care enhances offspring quality and fitness. In the proposed project, we will in a promiscuous species of nonhuman primates (1) test the benefits in terms of increased mating and reproductive success that a male can reap from investing in young either via mating effort and mate attraction or via true paternal care for related young. Next, we will (2) investigate a potential tradeoff between male parenting and mating effort and a potential switch in the tactics as the relative payoffs from either effort may change across a male’s life span or with status changes. Finally, we will (3) crucially add to the research on male care by assessing the fitness consequence of care for the offspring in a promiscuous system. We address these aims by leveraging a large long-term data set on male care and sexual behavior, short- and long-term benefits of care for young (e.g. age at maturation, survival), and genetic data on relatedness collected since 2006 on our study populations of Assamese macaques living in their natural habitat in northeastern Thailand and characterized by a promiscuous mating system with low level of paternity certainty.