Ecology and evolution of young species in sympatry

生物多样性在世界各地和加拿大有很大的差异，对加拿大人来说发挥着重要的功能和服务。当一个物种的种群彼此分离时，生物多样性就形成了，通常是在地理隔离（异地分布）中，最终又回到二次接触和重叠（同域分布）中，增加了当地和区域的生物多样性。我们研究的重点是次级同域性-年轻物种如何生活在一起，以及它们如何影响彼此的生态和进化？这些问题的答案是重要的-如果我们要保护它，我们必须了解生物多样性是如何形成和维持的。拟议研究的具体目标是测试年轻物种之间的二次接触和同域性对（I）物种识别和（II）生态学特征的影响。我们使用鸟类来解决这些问题，因为鸟类的分布，分类和进化关系比任何其他群体都更好。(I)物种识别特征-我们以前的工作记录了物种识别（颜色模式和歌曲）中涉及的特征更大的分歧时，密切相关的鸟类物种生活在同域。我们建议使用比较和实验研究来解释这种模式（杂交，侵略，信号干扰，通过生态性状的间接选择）之间的替代假设进行测试。(II)生态特征-我们以前对年轻物种生态学的研究表明，密切相关的鸟类最初使用相似的栖息地和重叠的繁殖区域，然后在栖息地使用上出现分歧。我们将测试字符位移假说解释栖息地的分歧，使用实验来检查健身成本和选择压力对年轻的物种，生活在一起，代表三个不同的鸣禽家庭。我们的研究将共同测试年轻物种之间的相互作用在生物多样性形成过程中的重要性，提供重要的见解如何以及密切相关的物种如何影响彼此的生态和进化，以及更广泛地说，密切相关的物种之间的相互作用如何促进或限制当地的生物多样性。

Biodiversity varies dramatically across the world and Canada, and performs important functions and services for Canadians. Biodiversity forms when populations of one species diverge from one another, typically in geographic isolation (allopatry), and eventually come back into secondary contact and overlap (sympatry), augmenting local and regional biodiversity. The focus of our research is secondary sympatry - how do young species live together, and how do they influence each other's ecology and evolution? An answer to these questions is important - we must understand how biodiversity forms and is maintained if we are to protect it. The specific objective of the proposed research is to test the consequences of secondary contact and sympatry among young species for traits involved in (I) species recognition and (II) ecology. We use birds to address these questions because the distribution, taxonomy, and evolutionary relationships of birds are better known than any other group. (I) Species Recognition Traits - Our previous work documented greater divergence in traits involved in species recognition (colour patterns and songs) when closely related species of birds live in sympatry. We propose to test among alternative hypotheses to explain this pattern (hybridization, aggression, signal interference, indirect selection through ecological traits) using comparative and experimental studies. (II) Ecological Traits - Our previous work on the ecology of young species suggests that closely related birds initially use similar habitats and overlap breeding territories, and then subsequently diverge in habitat use. We will test the Character Displacement Hypothesis to explain habitat divergence, using experiments to examine fitness costs and selective pressures acting on pairs of young species that live together, representing three distinct families of songbirds. Together, our research will test the importance of interactions among young species during the formation of biodiversity, providing important insights into how and how often closely related species influence each others' ecology and evolution, and, more broadly, how interactions among closely related species promote or constrain local biodiversity.