Polyandrous females found fitter populations
Polyandrous females found fitter populations
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DOI：
10.1111/jeb.12448
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发表时间：
2014-09-01
影响因子：
2.1
通讯作者：
Holman, L.
中科院分区：
文献类型：
--
作者：
Power, D. J.;Holman, L.
雌性的多次交配（一妻多夫制）需要一个进化的解释，因为它在许多物种中都有适应成本。当交配的雌性独自分散到一个新的栖息地时，它们的后代可能别无选择，只能与它们的兄弟姐妹交配，从而导致近亲繁殖的衰退。然而，一妻多夫制雌性的一些后代可能只有半兄弟姐妹，当孤立的兄弟姐妹群体只以对方为配偶时，这就减少了近亲繁殖的沮丧。我们研究了一妻多夫制对一妻多夫制的好处，方法是启动多个基因隔离的斑纹甲虫种群，每个种群由一个雌性甲虫建立，每个雌性甲虫从一个或两个雄性甲虫那里获得完整的射精。双受精雌虫的F4和F5后代比单受精雌虫的后代数量更多，从卵到成虫的存活率更高。无论甲虫是在它们的标准食物来源上饲养，还是在不那么有利的食物来源上饲养，这种健康效益都是相似的。我们的研究结果表明，一妻多夫制的雌性在近亲繁殖的创始种群中产生更健康的后代，因此一妻多夫制可能影响运动生态学和入侵生物学。
Multiple mating by females (polyandry) requires an evolutionary explanation, because it carries fitness costs in many species. When mated females disperse alone to a new habitat, their offspring may have no option but to mate with their siblings and incur inbreeding depression. However, some of the offspring of polyandrous females may only be half siblings, reducing inbreeding depression when isolated groups of siblings only have each other as mates. We investigated this putative benefit of polyandry over monandry by initiating multiple genetically isolated populations of Callosobruchus maculatus beetles, each founded by a single female, who received a complete ejaculate from either one or two males. The early generations had comparable fitness, but the F4 and F5 descendants of doubly inseminated females were more numerous and had higher egg-to-adult survival than the descendants of singly inseminated females. This fitness benefit was of similar magnitude whether beetles were reared on their standard food plant, or on a less favourable food source. Our results suggest that polyandrous females produce fitter descendants in inbred founder populations and therefore that polyandry may affect movement ecology and invasion biology.