Dimensions: Collaborative Research: Connecting the proximate mechanisms responsible for organismal diversity to the ultimate causes of latitudinal gradients in species richness.

物种多样性的纬度梯度是自然界最显著的生物地理格局之一，几乎所有种群的物种丰富度都在赤道地区达到顶峰。尽管对物种多样性纬度梯度的起源和维持作出了相当大的努力，但存在许多潜在的相互作用、非互斥的假说，没有出现单一的压倒一切的解释。然而，多个假设将纬度多样性梯度与温带和热带环境之间生物相互作用强度的假定梯度联系起来。虽然生物相互作用被认为在生物多样性的起源和维持中发挥了重要作用，并可能推动热带地区适应和物种形成的速度增加，但这一假说实际上仍未得到检验。为了弥补这一差距，将结合实地研究，对快速多样化的蝴蝶谱系中颜色、视觉和气味的适应性表型变化背后的进化机制进行全面分析。了解影响生物多样性时空格局的生态和进化过程是生物学的中心目标，也是濒危物种管理的一个日益重要的方面，特别是在全球气候快速变化的时期。这项建议将美国和拉丁美洲的生物多样性研究人员联系起来，并将导致持续的国际合作；通过有针对性的招聘，扩大妇女和少数民族进入STEM领域的机会；各机构和国家之间的大量就业机会；以及加强公众对生物多样性科学和全球生物多样性威胁的了解。

The latitudinal gradient in species diversity is one of the most striking biogeographic patterns in nature, with species richness peaking in equatorial regions for nearly all groups. Despite considerable effort to understand the origin and maintenance of latitudinal gradients in species diversity, a multitude of potentially interacting, non-mutually exclusive hypotheses exist, and no single over-riding explanation has emerged. However, multiple hypotheses link the latitudinal diversity gradient to a presumed gradient in the strength of biotic interactions between temperate and tropical environments. While biotic interactions are believed to play a major role in the origin and maintenance of diversity and may drive increased rates of adaptation and speciation in tropical regions, this hypothesis remains virtually untested. To bridge this gap, a comprehensive analysis of the evolutionary mechanisms underlying adaptive phenotypic variation in color, vision, and smell across a rapidly diversifying lineage of butterflies will be performed together with field-studies. Understanding the ecological and evolutionary processes that shape temporal and spatial patterns of biodiversity is a central goal of biology, and an increasingly important facet of the endangered species management, particularly in a time of rapid global climate change. This proposal links biodiversity researchers across the US and Latin America, and will lead to sustained international collaboration; broadened access to STEM fields for women and minorities through targeted recruitment; substantial employment opportunities across institutions and countries; and an enhanced public understanding of biodiversity science and threats to global biodiversity.