Collaborative Research: LTREB Renewal: Long-Term Dynamics of Amphibian Populations Following Disease-Driven Declines

合作研究：LTREB 更新：疾病驱动的衰退后两栖动物种群的长期动态

• 批准号: 2133399
• 负责人: Thomas Smith
• 金额: $ 37.33万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-05-01 至 2027-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2133399&HistoricalAwards=false
• 关键词: Collaborative; Research; LTREB; Renewal; Long

This project will examine the processes of invasion of a novel pathogen into a population for the case of a fungal pathogen that causes the disease chytridiomycosis in frogs and salamanders. Outbreaks of emerging infectious diseases are increasingly recognized as major threats, not just to human populations but also to wildlife, and they increasingly threaten global biodiversity. The initial invasion of a novel pathogen into a susceptible host population can cause a disease outbreak resulting in high levels of mortality and declines in population size. When this happens, natural selection can occur for both the host and pathogen populations resulting in evolutionary changes in the host's susceptibility and tolerance to infection by the pathogen and the pathogen's ability to damage the host (virulence). These changes can in turn determine whether the host population can persist and recover from the disease. Understanding these evolutionary processes is crucial in development of conservation strategies for threatened species. Chytridiomycosis has had catastrophic effects on amphibians worldwide, and has been linked to numerous species extinctions in recent decades and many more species at risk. The researchers will investigate the patterns of evolutionary change in both the pathogen and the host (mountain yellow-legged frogs), following the invasion of the disease into hundreds of high elevation lakes in the California Sierra Nevada. This project will contribute to the understanding of the role of infectious diseases, such as chytridiomycosis, as agents of evolutionary change in natural populations. It will provide critical information to state and federal agencies, facilitating endangered species recovery and will train and educate undergraduates, graduate students, and the general public.This research builds on data from a long-term study of the population dynamics of mountain yellow-legged frogs (Rana sierrae and Rana muscosa) in the complex landscape of the California Sierra Nevada, and the affects of Batrachochytrium dendrobatidis (Bd) as it has invaded and spread through hundreds of frog populations. In most cases, invasion of Bd results in outbreaks of the disease chytridiomycosis, rapid frog population declines, and local extinctions. In some cases, long-term persistence of frog populations occurs with Bd in an enzootic state in which the impact of the pathogen is greatly reduced. The research will extend and leverage 25 years of host population and disease data and archived genetic samples from R. sierrae/R. muscosa and Bd. These resources will provide insight into how populations of both host and pathogen change during the transition from pre-pathogen arrival, to disease outbreak, to enzootic disease, to potential recovery of the pre-disease host population abundances. This dataset will be used to investigate the genetic basis for differences in host resistance/tolerance and pathogen virulence. Cutting-edge genomic analysis of existing frog and fungal samples will complement laboratory experiments on Bd virulence and frog susceptibility using Bd cultures and frog mucosal samples from wild host populations. Continued surveys of wild host populations will identify new disease outbreaks and describe the transition from initial outbreak to persistent enzootic state.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.

该项目将检查新的病原体入侵人群中的过程，以导致青蛙和萨拉曼氏菌中疾病造成胸骨菌病的真菌病原体。新兴的传染病的爆发越来越多地被认为是主要威胁，不仅是人类人群，而且对野生动植物的爆发，它们越来越威胁到全球生物多样性。新型病原体最初入侵易感宿主人群可能导致疾病爆发，导致高死亡率和人口规模下降。当发生这种情况时，宿主和病原体种群可能会发生自然选择，从而导致宿主的敏感性和耐受性因病原体的感染以及病原体损害宿主的能力（毒力）而发生变化。这些变化反过来可以决定宿主人群是否可以持续并从疾病中恢复。了解这些进化过程对于发展受威胁物种的保护策略至关重要。剖腹菌病对全世界的两栖动物产生了灾难性的影响，并且与近几十年来的许多物种灭绝有关，还有更多的物种处于危险之中。研究人员将研究病原体和宿主（山黄青蛙）进化变化的模式，因为该疾病入侵了加利福尼亚州内华达州的数百个高海拔湖泊。该项目将有助于理解传染病的作用，例如乳腺癌，作为自然种群进化变化的药物。它将为州和联邦机构提供关键信息，促进濒危物种的恢复，并将培训和教育本科生，研究生和公众。这项研究基于对山黄色青蛙的人口动态的长期研究（Rana Sierrae and Rana Muscosa）的长期研究。树突状（BD）已经入侵并通过数百名青蛙种群传播。在大多数情况下，BD入侵导致疾病造成疾病的爆发，快速青蛙种群下降和局部灭绝。在某些情况下，青蛙种群的长期持久性发生在BD状态下，在这种状态下，病原体的影响大大降低了。这项研究将扩展并利用25年的寄主人群和疾病数据以及R. sierrae/r的存档遗传样本。 Muscosa和Bd。这些资源将洞悉宿主和病原体的种群如何在从病原体到达，疾病爆发到enzoote疾病到潜在恢复前疾病前宿主宿主种群丰度的过渡过渡期间如何变化。该数据集将用于研究宿主抗性/耐受性和病原体毒力差异的遗传基础。对现有青蛙和真菌样品的尖端基因组分析将使用来自野生寄主种群的BD培养物和青蛙粘膜样品进行有关BD毒力和青蛙敏感性的实验室实验。对野生寄主人群的持续调查将确定新的疾病暴发，并描述从初步爆发到持续的Enzootic国家的过渡。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的评估评估来支持的。

项目成果

Rapid Evolution of Resistance and Tolerance Leads to Variable Host Recoveries following Disease-Induced Declines

• DOI: 10.1086/729437
• 发表时间: 2024-05-01
• 期刊: AMERICAN NATURALIST
• 影响因子: 2.9
• 作者: Wilber，Mark Q.;DeMarchi，Joseph A.;Streipert，Sabrina
• 通讯作者: Streipert，Sabrina

Host density has limited effects on pathogen invasion, disease‐induced declines and within‐host infection dynamics across a landscape of disease

宿主密度对病原体入侵、疾病引起的衰退以及整个疾病领域的宿主内感染动态的影响有限

• DOI: 10.1111/1365-2656.13823
• 发表时间: 2022
• 期刊: Journal of Animal Ecology
• 影响因子: 4.8
• 作者: Wilber, Mark Q.;Knapp, Roland A.;Smith, Thomas C.;Briggs, Cheryl J.
• 通讯作者: Briggs, Cheryl J.

Rana sierrae (Sierra Nevada Yellow-legged Frog) Behavior and Diet

内华达黄腿蛙（Rana sierrae）的行为和饮食

• 发表时间: 2022
• 期刊: Herpetological review
• 作者: Smith, Thomas C.;Knapp, Roland A.;Imperato, John;Miller, Kira;Rose, Dylan
• 通讯作者: Rose, Dylan

Revisiting conservation units for the endangered mountain yellow-legged frog species complex (Rana muscosa, Rana sierrae) using multiple genomic methods

• DOI: 10.1007/s10592-023-01568-5
• 发表时间: 2023-09
• 期刊: Conservation Genetics
• 影响因子: 2.2
• 作者: Allison Q. Byrne;Andrew P. Rothstein;Lydia L. Smith;Hannah Kania;Roland A. Knapp;Daniel M. Boiano