Dissesrtation Research: A Cophylogenetic Analysis of Avian Hosts and their Parasites: Toucans (Aves: Piciformes) and Chewing Lice (Insecta: Pthiraptera)

论文研究：鸟类宿主及其寄生虫的共系统发育分析：巨嘴鸟（鸟纲：Piciformes）和咀嚼虱（昆虫纲：Pthiraptera）

• 批准号: 0104919
• 负责人: Frederick Sheldon
• 金额: $ 0.81万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0104919&HistoricalAwards=false
• 关键词: Dissesrtation; Research; Cophylogenetic; Analysis; Avian

A cophylogenetic analysis of avian hosts and their parasites: toucans(Aves: Piciformes) and chewing lice (Insecta: Pthiraptera) I am using nuclear and mitochondrial DNA sequences to reconstruct the phylogenetic history of an avian host group (Ramphastos toucans) and two of its parasitic chewing louse genera (Austrophilopterus and Menecanthus), which differ in life history characteristics. The object of this study is to determine how parasite groups with different ecological, behavioral and morphological characteristics respond to identical geographical and habitat perturbations (diversification and speciation of the host group). I will compare host and parasite histories by superimposing the phylogenies of the parasites and their hosts to determine whether or not parasite lineages with differences in ecology, behavior, and morphology respond similarly to speciation events in their hosts. If differences in the life history of the chewing lice are important, the different parasite lineages should vary in their degrees of cospeciation (parallel speciation). However, ifparasite lineages respond to host isolation events similarly, then one would expect the phylogenetic trees of the two parasite lineages to be congruent. Insights gained via this simple system should shed light on patterns of speciation in more complex systems of free-living organisms. Phylogenetic studies can answer important questions about speciation. However, one problem faced by phylogeneticists is that, when studying free-living organisms, they often lack nformation about the history of the study organism's habitats and geographic distribution. Thus, a usefulfirst step in phylogenetic studies is to reconstruct this history. Cophylogenetic studies of hosts and their parasites do this by superimposing the parasite phylogeny onto the phylogeny of the host. Speciation events in the host group are analogous to biogeographic vicariant events (e.g., when geographic barriers islolate opulations leading to speciation). Speciation, or lack thereof, in the parasites represents a response to geographic and ecological changes caused by host speciation events (vicariant events). By comparing parasites with different ecological, morphological, and behavioral characteristics we will begin to understand how these different life history characteristics affect the process of speciation.

鸟类宿主及其寄生虫巨嘴鸟和咀嚼虱的同源发生分析 我使用核和线粒体DNA序列重建的鸟类宿主组（Ramphaelus巨嘴鸟）和两个寄生咀嚼虱属（Austrophilopterus和Menecanthus），不同的生活史特征的系统发育史。 本研究的目的是确定不同的生态，行为和形态特征的寄生虫群体如何应对相同的地理和栖息地扰动（多样化和物种形成的主机组）。 我将比较主机和寄生虫的历史，通过叠加寄生虫和它们的主机的物种形成，以确定是否寄生虫谱系的生态，行为和形态的差异，在其主机的物种形成事件作出类似的反应。 如果咀嚼虱生活史的差异是重要的，那么不同的寄生虫谱系在共同物种形成（平行物种形成）的程度上应该有所不同。 然而，如果寄生虫谱系对宿主隔离事件的反应相似，那么人们会期望两种寄生虫谱系的系统发育树是一致的。 通过这个简单的系统获得的见解应该阐明更复杂的自由生活有机体系统中的物种形成模式。系统发育研究可以回答有关物种形成的重要问题。然而，遗传学家面临的一个问题是，当研究自由生活的生物体时，他们往往缺乏关于研究生物体栖息地和地理分布历史的信息。 因此，系统发育研究的第一步是重建这段历史。宿主及其寄生虫的同源发生研究通过将寄生虫的同源发生叠加到宿主的同源发生上来实现这一点。宿主群中的物种形成事件类似于地理替代事件（例如，当地理屏障隔离导致物种形成时）。 寄生虫的物种形成或缺乏物种形成代表了对宿主物种形成事件（替代事件）引起的地理和生态变化的反应。 通过比较具有不同生态、形态和行为特征的寄生虫，我们将开始了解这些不同的生活史特征如何影响物种形成的过程。