SG: Linking climate to global biogeographical patterns and diversification rates in ice-crawlers

冰爬行动物是不会飞的昆虫，专门生活在寒冷的环境中。它们生活在北美的高山地区，人们对它们的生物学和进化知之甚少。由于它们生活在高山冰川附近的独特习惯，这些冰川不断扩大和缩小，冰爬行动物是研究气候变化长期后果的天然模型。这项研究将探索两个主要的，到目前为止基本上没有答案的问题：气候如何影响物种的多样性和多样化？以及：随着时间的推移，物种如何改变它们对气候的生理耐受性？这项研究的结果将大大增加我们对物种对不断变化的环境的适应性反应的总体理解。这项研究将由在美国国家公园向公众宣传的努力、对高中生和大学生的培训以及可能在中学实施的以探究为基础的昆虫科学课程的发展来补充。这项建议的科学目的是测试地理隔离和气候生态位演变在山地生物多样性产生中的重要性，从而促进对山地生态系统中产生高度地方性的机制的认识。在上新世-更新世冰川作用下，山地类群的多样性有所增加，但气候生态位演化是否对山地类群的持久性和多样性起作用尚不清楚。事实上，地理隔离和生态位保守性被认为是气候驱动山区谱系多样化的主要机制。本研究将收集基因组数据，并为整个昆虫目——昆虫生命树中一个尚未得到充分研究的谱系——提供一个全面的系统发育。此外，生物地理和多样化率分析将检验气候波动在产生冰爬行动物多样性方面的作用。生态生理数据，包括热耐受性、热偏好和水分损失率，将在同域、不同环境梯度和异域中发生的分类群对中进行比较。总的来说，这些分析将测试生态位进化（与系统发育保守主义相反）是否有助于山地多样性。这项研究将对进化和生态学研究的一个主要目标取得进展，即了解不同地区和分类群体的生态分化率如何变化，以及谱系经历适应性辐射的条件。研究结果将发表在同行评议的期刊上，并在科学会议上发表。

Ice-crawlers are flightless insects that specialize in living in cold environments. They occur in high mountain areas in North America, and little is known about their biology and evolution. Because of their unique habit of living in areas near alpine glaciers, which constantly expand and retract, ice-crawlers are a natural model to study the long-term consequences of climate variation. This research will explore two major, and so far largely unanswered questions: How does climate influence the diversity and diversification of species? And: How do species change their physiological tolerance in response to climate over time? Results from this research will greatly increase our general understanding of adaptive responses of species to changing environments. This research will be complemented by outreach efforts to the public at U.S. National Parks, the training of high school and university students, as well as the development of inquiry-based science curricula involving insects that may be implemented in middle schools.The scientific aim of this proposal is to test the importance of geographical isolation and climatic niche evolution in the generation of montane biodiversity, thus advancing knowledge of the mechanisms that generate high levels of endemism in montane ecosystems. Montane lineage diversity increased in response to Pliocene-Pleistocene glaciations, but it is not clear whether climatic niche evolution played a role in the persistence and diversification of montane taxa. Indeed, geographical isolation and niche conservatism are considered the primary mechanisms of climate-driven lineage diversification in montane regions. This proposed research would collect genomic data and provide a comprehensive phylogeny for the entire insect order Grylloblattodea, an understudied lineage in the insect tree of life. Additionally, biogeographic and diversification rate analyses would test the role of climate fluctuations in generating ice-crawler diversity. Ecophysiological data, including thermal tolerance, thermal preference, and water loss rates, will be compared in taxon pairs occurring in sympatry, across environmental gradients, and in allopatry. Collectively, these analyses will test whether niche evolution, as opposed to phylogenetic conservatism, contribute to montane diversity. This research would make progress on a major goal of evolutionary and ecological research, that is to understand how rates of ecological divergence vary across regions and taxonomic groups, as well as the conditions under which lineages undergo adaptive radiations. The results will be published in peer-reviewed journals and presented at scientific meetings.