Benefits of multiple mates in the cricket Gryllus bimaculatus
Benefits of multiple mates in the cricket Gryllus bimaculatus
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DOI：
10.1111/j.1558-5646.1998.tb02252.x
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发表时间：
1998-12-01
期刊：
影响因子：
3.3
通讯作者：
Wedell, N
中科院分区：
文献类型：
--
作者：
Tregenza, T;Wedell, N
尽管一妻多夫对于性选择很重要，但雌性经常与多个雄性交配的原因仍然知之甚少。人们提出了许多遗传益处，基于这样的想法，即通过多交配，雌性增加了其后代由遗传上更兼容或更优秀的雄性生育的可能性。如果某些雄性本质上具有“良好基因”，那么任何与它们交配的雌性都会产生优秀的后代。或者，如果某些雄性具有与特定雌性不相容的遗传因素，那么如果这些雄性的精子不太可能使她的卵子受精，那么她可能会从一妻多夫制中受益。我们在蟋蟀 Gryllus bimaculatus（直翅目：蟋蟀科）中检验了这些假设。通过为雌性分配相同数量的交配次数但不同数量的交配，我们研究了交配数量对雌性繁殖力以及短期和长期后代健康的影响。这表明交配数量对产卵数量没有影响。然而，卵的孵化成功率随着交配数量的增加而增加。这种效应不能归因于非遗传效应，例如一妻多夫可能会减少雌性收到的精子数量或受精能力的差异，因为接受一半交配次数的对照组显示孵化成功率没有下降。治疗后，后代的存活率、成年体重、大小或发育时间没有差异。当雄性与几只不同的雌性交配时，雄性个体之间在其配偶卵的孵化成功率方面不存在可重复的差异。这表明，一妻多夫雌性孵化成功率的提高并不是因为某些雄性具有提高卵子活力的基因，无论其配偶如何。相反，我们的结果支持这样的假设：某些雄性在基因上与某些雌性更相容，并且这通过来自更相容的雄性的精子的差异受精成功率来驱动一妻多夫制。
Despite the importance of polyandry for sexual selection, the reasons why females frequently mate with several males remain poorly understood. A number of genetic benefits have been proposed, based on the idea that by taking multiple mates, females increase the likelihood that their offspring will be sired by genetically more compatible or superior males. If certain males have intrinsically "good genes," any female mating with them will produce superior offspring. Alternatively, if some males have genetic elements that are incompatible with a particular female, then she may benefit from polyandry if the sperm of such males are less likely to fertilize her eggs. We examined these hypotheses in the held cricket Gryllus bimaculatus (Orthoptera: Gryllidae). By allocating females identical numbers of matings but different numbers of mates we investigated the influence of number of mates on female fecundity, and both short- and long-term offspring fitness. This revealed no effect of number of mates on number of eggs laid. However, hatching success of eggs increased with number of mates. This effect could not be attributed to nongenetic effects such as the possibility that polyandry reduces variance in the quantity or fertilizing ability of sperm females receive, because a control group receiving half the number of copulations showed no drop in hatching success. Offspring did not differ in survival, adult mass, size, or development time with treatment. When males were mated to several different females there were no repeatable differences between individual males in the hatching success of their mate's eggs. This suggests that improved hatching success of polyandrous females is not due to certain males having genes that improve egg viability regardless of their mate. Instead, our results support the hypothesis that certain males are genetically more compatible with certain females, and that this drives polyandry through differential fertilization success of sperm from more compatible males.