Data from: The effect of parasitism and interpopulation hybridization on Aedes albopictus (Diptera: Culicidae) fitness

Recent research in mosquito population genetics suggests that
interpopulation hybridization has likely contributed to the rapid spread
of the container-breeding mosquitoes. Here, I used laboratory experiments
to investigate whether interpopulation Aedes (Stegomyia) albopictus
(Skuse) F1 and F2 hybrids exhibit higher fitness than parental
populations, and whether hybrid mosquito performance is related to
infection by the coevolved protozoan parasite Ascogregarina taiwanensis
(Lien and Levine). Overall, there were significant differences in
development time, wing length, and survival between the two parental
mosquito populations, but no difference in per capita growth rate r.
Hybrid mosquitoes were generally intermediate in phenotype to the
parentals, except that F2 females were significantly larger than the
midparent average. In addition, As. taiwanensis parasites produced fewest
oocysts when they were reared in hosts of hybrid origin. These data
suggest that hybridization between previously isolated mosquito
populations can result in slight increases in potential mosquito
reproductive success, via increased hybrid body size, and via the
temporary escape from coevolved parasites. These findings are significant
because studies have shown that even slight hybrid vigor can have positive
fitness consequences for population persistence. Although this was a
laboratory experiment extending only to the F2 generation, many other
invasive insects also carry coevolved parasites, and thus the patterns
seen in this mosquito system may be broadly relevant.

近年来蚊虫种群遗传学领域的研究表明，种群间杂交可能推动了容器孳生蚊虫的快速扩散。本研究通过实验室实验，探究种群间白纹伊蚊（Aedes (Stegomyia) albopictus）的子一代（F1）与子二代（F2）杂交个体是否比亲本种群具有更高的适合度，同时探究杂交蚊虫的表现是否与其感染协同进化原生动物寄生虫台湾艾美格孢虫（Ascogregarina taiwanensis (Lien and Levine)）相关。整体而言，两个亲本蚊虫种群在发育时长、翅长与存活率上存在显著差异，但单位个体增长率r无显著差异。杂交蚊虫的表型通常介于双亲之间，唯有子二代雌蚊的体型显著大于双亲平均水平。此外，台湾艾美格孢虫在杂交起源的宿主体内发育时，产生的卵囊数量最少。上述数据表明，此前地理隔离的蚊虫种群间的杂交，可通过增大杂交个体体型、使其暂时摆脱协同进化寄生虫的感染，小幅提升蚊虫潜在的繁殖成功率。该研究结果具有重要意义，因为已有研究证实，即便微弱的杂种优势也能对种群存续产生积极的适合度效应。尽管本实验仅开展至子二代阶段且为实验室环境下的研究，但其他诸多入侵昆虫同样携带协同进化寄生虫，因此本蚊虫系统中观察到的规律或具有广泛的参考价值。