BEE: Eco-evolutionary dynamics of disease-induced apex predator declines

该项目将研究传染病的传播如何影响病原体和宿主的共同进化，以及这些变化如何影响动物群落的其他部分。新出现的传染病和全球生物多样性的丧失是21世纪生命科学面临的两大挑战。澳大利亚标志性的塔斯马尼亚魔鬼的减少就是这两种威胁共同威胁一个物种的一个例子。此外，随着这些大型捕食者的减少，其他物种在食物链中的作用发生了变化，这可能导致其他物种的二次减少和灭绝，从而导致生物多样性的丧失。这些群落的变化可以反馈给捕食者自己，导致发育时间和繁殖的变化。因此，研究顶级捕食者的减少如何导致食物网、种群密度和与其相互作用的物种进化的变化是至关重要的。通过向公众推广，这项研究将增加对传染病如何影响生物群落和影响生物多样性的了解。它还将为美国研究生和博士后学者在国际环境中提供培训机会。袋獾及其致命的传染性癌症——袋獾面部肿瘤病（devil facial tumor disease， DFTD）是阐明顶级捕食者减少对群落动态影响的理想研究体系。DFTD的东向西传播提供了一个罕见的自然实验，以测试塔斯马尼亚州魔鬼数量下降程度的时间变化如何影响社区动态。魔鬼确实是群落的建筑师，它们的减少会导致中掠食者释放的直接影响，然后通过食物网连锁反应，间接导致本地物种的二次减少。该研究将结合生态学和进化理论来预测魔鬼和DFTD的共同进化相互作用将如何影响当前和未来的魔鬼种群密度。然后，这些预测将被插入（结构方程）模型中，该模型将对塔斯马尼亚魔鬼食物网中生态相互作用的实地研究纳入下降梯度中。这些群落水平变化对袋獾生活史进化的反馈将通过对雌性袋獾快速发育轨迹和早熟繁殖基础的基因组研究进行评估。利用景观基因组学研究评估中捕食者和猎物的进化反馈，以测试魔鬼密度变化对多代基因流动和适应潜力的影响。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project will study how the spread of an infectious disease can affect the co-evolution of the pathogen and the host, and who those changes can create changes in the rest of the animal community. Emerging infectious diseases and the global loss of biodiversity are two leading challenges for the life sciences in the 21st century. Declines of the iconic Tasmanian devil in Australia represent an example of these two threats acting together to endanger a species. Additionally, as such large predators decline, the role of other species shifts in the food chain, which can lead to loss of biodiversity via secondary declines and extinctions of other species. These community changes can then feed back on the predator themselves, resulting in changes in developmental timing and reproduction. Thus, it is critical to study how losses of top predators lead to changes in food webs, population densities, and evolution of species with which they interact. Through outreach to the general public, this study will increase understanding of how infectious diseases affect biological communities and influence biodiversity. It will also provide training opportunities for US graduate students and post-doctoral scholars in an international setting.Tasmanian devils and their fatal transmissible cancer, devil facial tumor disease (DFTD), represents an ideal study system to elucidate the impacts of top predator losses on community dynamics. The east to west spread of DFTD provides a rare, natural experiment to test how temporal variation in extent of devil declines across Tasmania affects community dynamics. Devils are indeed community architects, the declines of which cause the direct effects of mesopredator release that then cascades through the food web to indirect secondary declines of native species. The research will bridge ecological and evolutionary theory to predict how co-evolutionary interactions of devils and DFTD will affect current and future devil population densities. These predictions will then be plugged into (structural equation) models that incorporate field studies of ecological interactions within the Tasmanian devil food web across the decline gradient. Feedbacks of these community-level changes on Tasmanian devil life history evolution will be evaluated with genomic study of the basis of a rapid developmental trajectory and precocial breeding in female devils. Evolutionary feedbacks on mesopredators and prey will be assessed using landscape genomics studies to test the influence of variation in devil density on gene flow and adaptive potential across multiple generations.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.