Sweet Andrew D, Johnson Kevin P
Illinois Natural History Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, 1816 S. Oak St., Champaign, IL 61820, United States.
Illinois Natural History Survey, Prairie Research Institute, University of Illinois at Urbana-Champaign, 1816 S. Oak St., Champaign, IL 61820, United States.
Mol Phylogenet Evol. 2016 Oct;103:122-132. doi: 10.1016/j.ympev.2016.07.018. Epub 2016 Jul 18.
Hosts-parasite interactions are plentiful and diverse, and understanding the patterns of these interactions can provide great insight into the evolutionary history of the organisms involved. Estimating the phylogenetic relationships of a group of parasites and comparing them to that of their hosts can indicate how factors such as host or parasite life history, biogeography, or climate affect evolutionary patterns. In this study we compare the phylogeny generated for a clade of parasitic chewing lice (Insecta: Phthiraptera) within the genus Columbicola to that of their hosts, the small New World ground-doves (Aves: Columbidae). We sampled lice from the majority of host species, including samples from multiple geographic locations. From these samples we sequenced mitochondrial and nuclear loci for the lice, and used these data to estimate phylogenetic trees and population networks. After estimating the appropriate number of operational taxonomic units (OTUs) for the lice, we used cophylogenetic analyses to compare the louse phylogeny to an existing host phylogeny. Our phylogenetic analysis recovered significant structure within the louse clade, including evidence for potentially cryptic species. All cophylogenetic analyses indicated an overall congruence between the host and parasite trees. However, we only recovered a single cospeciation event. This finding suggests that certain branches in the trees are driving the signal of congruence. In particular, lice with the highest levels of congruence are associated with high Andean species of ground-doves that are well separated altitudinally from other related taxa. Other host-parasite associations are not as congruent, and these often involved widespread louse taxa. These widespread lice did, however, have significant phylogeographic structure, and their phylogenetic relationships are perhaps best explained by biogeographic patterns. Overall these results indicate that both host phylogeny and biogeography can be simultaneously important in influencing the patterns of diversification of parasites.
宿主与寄生虫之间的相互作用丰富多样,了解这些相互作用的模式能够为深入探究相关生物的进化历史提供重要线索。估计一组寄生虫的系统发育关系,并将其与宿主的系统发育关系进行比较,可以揭示宿主或寄生虫的生活史、生物地理学或气候等因素如何影响进化模式。在本研究中,我们将寄生性咀嚼虱(昆虫纲:啮目)的一个分支——鸽虱属(Columbicola)的系统发育与它们的宿主——新大陆小型地鸽(鸟纲:鸠鸽科)的系统发育进行了比较。我们从大多数宿主物种中采集了虱子样本,包括来自多个地理位置的样本。从这些样本中,我们对虱子的线粒体和核基因座进行了测序,并利用这些数据估计系统发育树和种群网络。在估计了虱子合适的操作分类单元(OTU)数量后,我们使用共系统发育分析将虱子的系统发育与现有的宿主系统发育进行比较。我们的系统发育分析在虱子分支中发现了显著的结构,包括潜在隐存物种的证据。所有共系统发育分析均表明宿主树和寄生虫树总体上是一致的。然而,我们只发现了一次共物种形成事件。这一发现表明,树中的某些分支驱动了一致性信号。特别是,一致性水平最高的虱子与安第斯高地的地鸽物种相关,这些地鸽在海拔高度上与其他相关分类群有明显的隔离。其他宿主 - 寄生虫关联并不那么一致,这些关联通常涉及分布广泛的虱子类群。然而,这些分布广泛的虱子确实具有显著的系统地理学结构,它们的系统发育关系或许最好用生物地理学模式来解释。总体而言,这些结果表明宿主系统发育和生物地理学在影响寄生虫多样化模式方面可能同时起着重要作用。