Testing mating systems theory in a polygynous model system: the reindeer/caribou (Rangifer tarandus)

在一夫多妻模型系统中测试交配系统理论：驯鹿/驯鹿（Rangifer tarandus）

• 批准号: 327505-2013
• 负责人: Weladji, RobertBertrand
• 金额: $ 1.6万
• 依托单位: Concordia University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=526986
• 关键词: Testing; mating; systems; theory; polygynous

Over the past several decades, many models have attempted to develop a predictive framework for mating systems. However, quantifying sexual selection and testing mating systems theory in the field have proven difficult. My aim is to use an experimental approach to test the key predictions of mating systems theory. I will manipulate female density, food dispersion, and operational sex ratio (OSR) to assess how they influence mating group dynamics and mating tactics. Ungulates are excellent model systems to study the evolution of mating systems because they have the highest variability in sexual dimorphism, and because of their minimal paternal care and great variability in mating systems. I use reindeer (Rangifer tarandus) from an exceptional population where all individuals will be fitted GPS collars and manipulation is possible as my model system. Specifically we will test whether : (i) the average group size, the rate of fission, the rate of fusion, and patchiness (a measure of the degree to which females are clumped in space), increase with density; (ii) females aggregate at food patches, leading to higher average group size and patchiness in clumped than dispersed treatments; (iii) males mating strategy differs between the clumped and dispersed treatments, with resource defense in the clumped treatment and monopolization in the dispersed treatment, underlying the plasticity of mating strategies; (iv) the correlation between patchiness and the opportunity for sexual selection is positive; and whether (v) male-male aggression increases with OSR whereas female-female aggression decreases; and courtship rate decreases with OSR, because of increased male-male competition. By using a fully-controlled GPS-based population, my research will rigorously test key predictions of mating systems theory on reindeer and show whether the intensity of competition can be minimized by manipulating the local environment. The research has management implications by showing density-dependent influence on the distribution of male mating success and population productivity, and by providing information necessary for long term conservation. The work, therefore, provides insight into the mechanisms of population regulation.

在过去的几十年里，许多模型都试图为交配系统建立一个预测框架。然而，量化性选择和测试交配系统理论在该领域已被证明是困难的。我的目的是用实验的方法来检验交配系统理论的关键预测。我将操纵雌性密度、食物分散和操作性比（OSR）来评估它们如何影响交配群体动态和交配策略。有蹄类动物是研究交配系统进化的极好模型系统，因为它们在两性二态性方面具有最高的可变性，而且它们的父系照料最少，交配系统的可变性很大。我使用的驯鹿（Rangifer tarandus）来自一个特殊的种群，其中所有个体都将安装GPS项圈，并且可以作为我的模型系统进行操作。具体来说，我们将测试：(i)平均群体规模、裂变率、融合率和斑块（衡量女性在空间中聚集的程度）是否随着密度的增加而增加；（ii）雌性聚集在食物斑块上，导致成团处理的平均群体大小和斑块度高于分散处理；(3)雄性交配策略在集群和分散处理之间存在差异，集群处理表现为资源防御，而分散处理表现为资源垄断，表明雄性交配策略具有可塑性；（iv）斑块与性选择机会呈正相关；(v)男性与男性之间的攻击性是否会随着OSR的增加而增加，而女性与女性之间的攻击性是否会减少；求偶率随着OSR的增加而下降，因为雄性之间的竞争增加了。通过使用完全控制的基于gps的种群，我的研究将严格测试驯鹿交配系统理论的关键预测，并表明是否可以通过操纵当地环境来最小化竞争强度。该研究显示了密度对雄性交配成功率和种群生产力分布的影响，并为长期保护提供了必要的信息，从而对管理产生了影响。因此，这项工作提供了对人口调控机制的深入了解。