Collaborative Research: BEE: Bridging the ecology and evolution of East African Acacias across time and space: genomics, ecosystem, and diversification.

物种的物理属性和行为是由进化塑造的。这些特征决定了个体如何与环境(生态)相互作用，从而影响进化过程。因此，生态和进化密不可分。在进化和生态领域之间架起桥梁是具有挑战性的，因为所涉及的过程可以在相似的或非常不同的时间尺度上运行。非洲稀树草原相思树已经进化到在许多其他树种所不能容忍的恶劣条件下生存和繁殖。金合欢可以忍受火灾、干旱、长颈鹿和大象的食草性，以及来自其他植物的竞争。但金合欢过去如何适应这些条件，将影响它们对非洲大陆目前不断变化的环境的反应。这项研究的目的是全面了解非洲相思的进化史和生态分布，并探索物种特征和分布如何随着时间的推移而变化，以响应稀树大草原气候的变化。最终，这一知识将为预测相思栖息地将如何受到持续气候变化的影响提供信息。该项目不仅具有更广泛的社会效益，还将培养进化生物学、生态学、植物生理学和分子基因组学方面的本科生、研究生和博士后研究员。此外，该项目将扩大以塞伦盖蒂国家公园为特色的成功的生态学和进化论本科教学模块的内容和覆盖范围，并将与非洲的大学合作开始一门新的生物信息学培训课程。该项目将通过对性状反应和基因表达的直接生态实地测量，为多样化的系统发生方法架起桥梁。这些活动包括：(1)构建新的、详细的非洲相思树种和性状的系统发育历史和生态分布模型；(2)利用系统发育学分析，研究与草原综合症相关的选择、导入和基因家族扩展；(3)在坦桑尼亚阿鲁沙的一个普通花园实验中，测量相思树性状对草原综合症成分(干旱、火、草食、草竞争)的反应；以及(4)通过分析在坦桑尼亚的现场和对照温室实验中收集的相思树转录图谱，分析相思树种表型反应的分子方面。总而言之，这些相互关联的证据将提供有关稀树草原群落过去的演变、中新世在整个非洲迅速崛起的稀树草原，以及它可能对当前生态变化做出的反应的关键信息。这一奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

The physical attributes and behaviors of species are shaped by evolution. These traits determine how individuals interact with their environment (ecology) which then influences the course of evolution. Thus, ecology and evolution are inextricably intertwined. Bridging the fields of evolution and ecology is challenging because the processes involved can operate on similar, or very different, time scales. African savanna acacia trees have evolved to survive and reproduce under harsh conditions not tolerated by many other tree species. Acacias can tolerate fires, droughts, herbivory by giraffes and elephants, and competition from other plants. But how acacias have adapted to these conditions in the past will influence their response to the current changing environment on the African continent. The goal of this study is to develop a comprehensive understanding of the evolutionary history and ecological distribution of African acacias and to explore how species traits and distributions changed over time in response to change in the savanna climate. Ultimately, this knowledge will inform predictions about how acacia habitats will be affected by ongoing climate change. This project not only has broader societal benefit but also it will train undergraduate and graduate students and postdoctoral fellows in evolutionary biology, ecology, plant physiology, and molecular genomics. In addition, the project will expand the content and reach of a successful undergraduate teaching module of ecology and evolution featuring Serengeti National Park and will begin a new bioinformatics training course in partnership with universities in Africa.This project will bridge phylogenetic approaches to diversification with direct ecological field measurement of trait responses and gene expression. The activities include: (1) constructing new, detailed models of the phylogenetic history and ecological distribution of species and traits in the African Acacia Clade, (2) using phylogenomic analyses to study selection, introgression, and gene family expansion in relation to the Savanna Syndrome, (3) measuring acacia trait responses to Savanna Syndrome components (drought, fire, herbivory, grass competition) in a common garden experiment in Arusha, Tanzania, and (4) analyzing the molecular aspects of the phenotypic response through analysis of acacia transcriptomic profiles collected both on site in Tanzania and in controlled greenhouse experiments. Collectively, these linked lines of evidence will provide crucial information about the past evolution of the savanna community, the rapid rise of savannas across Africa that occurred in the Miocene, and its likely response to present ecological change.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.