Evolutionary ecology of parasite-host species interactions

寄生虫与宿主物种相互作用的进化生态学

• 批准号: RGPIN-2018-05304
• 负责人: Forbes, Mark
• 金额: $ 5.83万
• 依托单位: Carleton University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=745697
• 关键词: Evolutionary; ecology; parasite; host; species

Evolutionary ecology of parasite-host species interactions: host species use, evolution of resistance, and parasite aggregation.Much ink has been spilled about co-evolutionary interactions of parasites and their host species. That is, researchers are often interested in questions such as why some parasites and pathogen species are nasty, whereas others are relatively benign; or, why some parasites or pathogen species have broad host species ranges whereas others tend to be specialists, for a given stage of their life cycle. Parasites and pathogens are often seen as having the evolutionary upper hand over their hosts because of asymmetric selection. This is because parasites and pathogens often have shorter generation times than their hosts, have infective stages that are much more numerous than their hosts, and have an obligate dependence on host individuals for their growth, development and/or reproduction. However, this view belies the facts that parasites often share host resources with other species and also that many parasite species have several host species, even at single sites and over the same time frames. Concurrent multi-host, multi-parasite associations set the stage for diffuse ecological and evolutionary interactions amongst parasites and their hosts. Such diffuse interactions are likely common in nature, yet have received comparatively little attention. In this application, I will outline some of the more prominent hypotheses about intra- and interspecific variation in parasitism and host resistance and its relation to ecology of host species and host species range of parasitic organisms. My lab has a rich tradition in studying various species of dragonflies and their ectoparasitic mites to test such hypotheses. With my HQP, I will also address the evolutionary causes and importance of parasite aggregation on host species, which is deemed one of the general laws of ecological parasitology and which has implications for intra-and interspecific interactions among parasites. Tests and insights have become much stronger with the following: the advent of barcoding techniques, experimental approaches previously deemed difficult, geographical comparisons of species interactions, and equation-based models building on empirical results, all of which are proposed approaches for this grant cycle. Sample preparation and taxonomy is done in my lab; collaborators at Biodiversity Institute of Ontario and AgCan do barcoding. Experimental approaches are possible with CFI-funded Environmental Rooms and NSERC RTI-funded Zeiss microscope and Conviron incubators. We have sites chosen for the geographical studies and we have expertise with equation-based modeling. Students gain effective training from me, other HQP and collabotators with one to several experimental and statisitical techniques. (See CCV, Proposal and Attached Contributions for details).

寄生虫与宿主物种相互作用的进化生态学：宿主物种的利用、抗性的进化和寄生虫聚集。关于寄生虫与其宿主物种的共同进化相互作用已经有很多文章。也就是说，研究人员经常对诸如为什么某些寄生虫和病原体物种是令人讨厌的，而另一些则相对良性等问题感兴趣；或者，为什么某些寄生虫或病原体物种在其生命周期的特定阶段具有广泛的宿主物种范围，而另一些则往往是专家。由于不对称选择，寄生虫和病原体通常被认为在进化上优于宿主。这是因为寄生虫和病原体的世代时间通常比宿主短，感染阶段的数量比宿主多得多，并且其生长、发育和/或繁殖绝对依赖于宿主个体。 然而，这种观点掩盖了这样一个事实：寄生虫经常与其他物种共享宿主资源，而且许多寄生虫物种有多个宿主物种，即使是在单个地点和同一时间范围内。并发的多宿主、多寄生虫关联为寄生虫及其宿主之间的分散生态和进化相互作用奠定了基础。这种分散的相互作用在自然界中可能很常见，但受到的关注相对较少。在本申请中，我将概述一些关于寄生性和寄主抗性的种内和种间变异及其与寄主物种生态和寄生生物寄主物种范围的关系的一些更突出的假设。我的实验室在研究各种蜻蜓及其体外寄生螨以检验这些假设方面有着丰富的传统。 在我的 HQP 中，我还将阐述寄主物种上寄生虫聚集的进化原因和重要性，这被认为是生态寄生虫学的一般规律之一，并且对寄生虫之间的种内和种间相互作用具有影响。随着以下内容的出现，测试和见解变得更加有力：条形码技术的出现、以前认为困难的实验方法、物种相互作用的地理比较以及建立在经验结果基础上的基于方程的模型，所有这些都是本资助周期的拟议方法。样品制备和分类是在我的实验室完成的；安大略省生物多样性研究所和 AgCan 的合作者进行条形码工作。实验方法可以使用 CFI 资助的环境室和 NSERC RTI 资助的蔡司显微镜和 Conviron 培养箱来实现。我们选择了进行地理研究的地点，并且拥有基于方程的建模方面的专业知识。学生从我、其他总部和合作者那里获得有效的培训，掌握一到几种实验和统计技术。 （有关详细信息，请参阅 CCV、提案和附加贡献）。