Northern Michigan University, 1401, Presque Isle Ave, Marquette, MI 49855, United States.
Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia.
Mol Phylogenet Evol. 2023 Jun;183:107775. doi: 10.1016/j.ympev.2023.107775. Epub 2023 Mar 25.
The dynamic climate history that drove sea level fluctuation during past glacial periods mediated the movement of organisms between Asia and North America via the Bering Land Bridge. Investigations of the biogeographic histories of small mammals and their parasites demonstrate facets of a complex history of episodic geographic colonization and refugial isolation that structured diversity across the Holarctic. We use a large multi-locus nuclear DNA sequence dataset to robustly resolve relationships within the cestode genus Arostrilepis (Cyclophyllidea: Hymenolepididae), a widespread parasite of predominantly arvicoline rodents (voles, lemmings). Using this phylogeny, we confirm that several Asian Arostrilepis lineages colonized North America during up to four distinct glacial periods in association with different rodent hosts, consistent with taxon-pulse dynamics. A previously inferred westward dispersal across the land bridge is rejected. We also refine interpretations of past host colonization, providing evidence for several distinct episodes of expanding host range, which probably contributed to diversification by Arostrilepis. Finally, Arostrilepis is shown to be paraphyletic with respect to Hymenandrya thomomyis, a parasite of pocket gophers, confirming that ancient Arostrilepis species colonized new host lineages upon arriving in North America.
驱动过去冰期海平面波动的动态气候历史通过白令陆桥将亚洲和北美的生物进行了迁移。对小型哺乳动物及其寄生虫的生物地理学历史的研究表明，它们经历了一系列阶段性的地理殖民和避难所隔离，这在全北极地区构建了多样性。我们使用一个大型多基因核 DNA 序列数据集来可靠地解决 cestode 属 Arostrilepis（Cyclophyllidea：Hymenolepididae）内的关系，该属是一种广泛存在的主要以 arvicoline 啮齿动物（田鼠、旅鼠）为宿主的寄生虫。利用这个系统发育，我们证实了几个亚洲 Arostrilepis 谱系在与不同啮齿动物宿主相关的四个不同的冰川期期间殖民到了北美，这与分类脉冲动态一致。此前推断的通过陆桥向西扩散被拒绝。我们还改进了对过去宿主殖民的解释，提供了几个明显的宿主范围扩大的证据，这可能通过 Arostrilepis 导致了多样化。最后，Arostrilepis 相对于 Hymenandrya thomomyis（一种囊鼠寄生虫）是并系的，证实了古老的 Arostrilepis 物种在到达北美后，会殖民新的宿主谱系。
