Host association drives significant genetic divergence in the bed bug, Cimex lectularius

Genetic differentiation may exist among sympatric populations of a species due to long-term associations with alternative hosts (i.e., host-associated differentiation). While host-associated differentiation has been documented in several phytophagus insects, there are far fewer cases known in animal parasites. The bed bug, Cimex lectularius, a wingless insect, represents a potential model organism for elucidating the processes involved in host-associated differentiation in animal parasites with relatively limited mobility. In conjunction with the expansion of modern humans from Africa into Eurasia, it has been speculated that bed bugs extended their host range from bats to humans in their shared cave domiciles throughout Eurasia. C. lectularius that associate with humans have a cosmopolitan distribution, whereas those associated with bats occur across Europe, often in human-built structures. We assessed genetic structure and gene flow within and among populations collected in associatio...由于物种与不同宿主的长期共生关联，同一物种的同域种群（sympatric populations）间可能存在遗传分化，即宿主关联分化（host-associated differentiation）。尽管已有多项研究在多种植食性昆虫（phytophagus insects）中记录到宿主关联分化现象，但在动物寄生虫（animal parasites）中被报道的此类案例则相对稀少。无翅昆虫温带臭虫（Cimex lectularius）是一种极具潜力的模式生物（model organism），可用于解析迁移能力相对有限的动物寄生虫的宿主关联分化过程。结合现代人类从非洲向欧亚大陆的扩张历程，有研究推测臭虫曾在欧亚大陆共有的洞穴栖息环境中，将宿主范围从蝙蝠拓展至人类。寄生于人类的温带臭虫呈广布分布，而寄生于蝙蝠的种群则仅分布于欧洲，且常出现在人类建造的建筑内。我们对采集自相关宿主关联生境的种群内部及种群间的遗传结构（genetic structure）与基因流（gene flow）进行了评估……