Doctoral Dissertation Research: Socioendocrinology of Male Reproductive Strategies in the Siamang (Symphalangus Syndactylus)

这项研究旨在阐明塑造雄性灵长类动物行为和激素特征的进化力量。特别是，它将探讨男性内分泌和男性之间的竞争，父母的努力和女性生殖状态，在一夫一妻制和一妻多夫制交配系统的背景下之间的相关性。数据将来自行为观察和非侵入性激素采样的四个一夫一妻制和三个一妻多夫组的合趾猴（Hylobatidae：Symphalangus syndactylus）在苏门答腊（印度尼西亚）。这些数据将揭示灵长类动物许多引人注目和知之甚少的方面的共同进化，包括人类，社会和生殖生物学，如性内和性间攻击，配对和父亲照顾。这项工作的智力贡献分为四个广泛的领域：首先，这项研究将提供第一个激素数据的野生一夫一妻制和一妻多夫制（非人类）类人猿。这些交配系统是非常罕见的哺乳动物（约3%），因此，这些数据是必不可少的，为改善目前的哺乳动物的社会evolution.Second模型，本调查评估的激素和行为反应的配对结合男性不同的生殖挑战（内或外的社会群体的性竞争对手）。因此，这些数据将测试假设的重要作用，配偶守卫在人类男性竞争，并将扩大的广度理论，迄今为止只在人类中测试，如“配偶偷猎”。第三，父亲的照顾是一个显着的特征，人类行为生物学，但在灵长类动物中是例外。通过提供一个额外的双亲类人猿的数据，这项研究将使我们能够，第一次，评估这些人类模式的普遍性，并澄清与男性养育子女相关的条件和限制。最后，最近的实验数据表明，人类男性的行为受到女性生殖状态（通过视觉或嗅觉线索）的影响。评估相似的影响，将有助于理解的起源和功能的信号与隐藏排卵在人类和非人类灵长类动物。这也将有助于确定女性生殖状态影响男性社会和生殖行为的社会和生态条件。这项研究的一个更广泛的影响是它对保护工作的贡献：这项研究将增进对合趾猴人口统计学和种群动态的了解，并将提供对栖息地恶化和破碎化影响的准确评估。该项目将雇用和培训至少五名当地外地助理。此外，还将支持和监督印度尼西亚大学两名硕士生的实地考察。目前正在讨论在Way Canguk建立一所灵长类动物学野外学校的计划，以促进当地的教育/保护工作，并将通过同行审查的出版物和参加专业会议来传播结果。这将有助于指导未来的近因机制研究（例如，关注其他激素），心理相关因素，传播模式，以及这群社会一夫一妻制猿类的雌性生殖策略。最后，本项目将为获奖者提供广泛的现场内分泌学和实验室程序实践，并将扩大他可以教授的科目范围，以及他将为未来的工作场所带来的专业知识。

This research seeks to clarify the evolutionary forces shaping the behavioral and hormonal profiles of male primates. In particular, it will explore the correlations between male endocrinology and male-male competition, parental effort and female reproductive state, in the context of monogamous and polyandrous mating systems. Data will come from behavioral observation and non-invasive hormonal sampling of four monogamous and three polyandrous groups of siamangs (Hylobatidae: Symphalangus syndactylus) in Sumatra (Indonesia). Non-biohazardous hormonal extracts will be stored in the field and analyzed in the U.S.These data will shed light on the co-evolution of many striking and poorly understood aspects of primate, including human, social and reproductive biology, such as intra- and intersexual aggression, pair bonding and paternal care. The intellectual contributions of this work fall into four broad areas:First, this study will provide the first hormonal data on a wild monogamous and polyandrous (nonhuman) hominoid. These mating systems are extremely rare among mammals (about 3%), thus, these data are essential for the improvement of current models of mammalian social evolution.Second, this investigation evaluates the hormonal and behavioral responses of pair-bonded males to different reproductive challenges (sexual competitors within or outside the social group). These data will therefore test the hypothetically important role of mate guarding in human male competition, and will expand the breadth of theories so far tested only in humans, such as "mate poaching".Third, paternal care is a conspicuous feature of human behavioral biology, but rather exceptional among primates. By providing data on an additional biparental ape, this study will allow us, for the first time, to assess the generality of these human patterns, and clarify the conditions and constraints associated with male parenting.Finally, recent experimental data shows that human male behavior is affected by female reproductive state (through visual or olfactory cues). An evaluation of similar effects on siamangs will contribute to the understanding of the origin and function of signaling versus concealment of ovulation in human and non-human primates. It will also help determining the social and ecological conditions under which female reproductive status affect male social and reproductive behavior.One broader impact of this research is its contribution to conservation efforts: the study will improve the understanding of siamang demography and population dynamics, and will provide an accurate assessment of the impact of habitat deterioration and fragmentation.The project will employ and train at least five local field assistants. In addition, the fieldwork of two Masters students at the University of Indonesia will be supported and supervised. Plans are being discussed to establish a primatology field school at Way Canguk, to further local education/conservation efforts.Results will be disseminated through peer-reviewed publications and participation in professional meetings. This will help to guide future studies of proximate mechanisms (e.g. focusing on other hormones), psychological correlates, dispersal patterns, and female reproductive strategies in this group of socially monogamous apes.Finally, this project will provide the awardee's with extensive practice with field endocrinology and laboratory procedures, and it will broaden the range of subjects he can offer to teach, as well as the expertise that he will bring to future working places.