Do the benefits of polyandry scale with outbreeding?
Do the benefits of polyandry scale with outbreeding?
复制标题
DOI：
10.1093/beheco/arv103
复制
发表时间：
2015-09
期刊：
影响因子：
--
通讯作者：
Shuker DM
中科院分区：
文献类型：
--
作者：
Burdfield-Steel ER;Auty S;Shuker DM
交配可能既昂贵又危险。尽管如此，许多物种的雌性通常会不止一次交配，并与不同的雄性交配。我们发现，雌性种子虫只有在她的配偶中有一人是不同物种的情况下，才能从与1只以上的雄性交配中受益。雌性只需要与自己的物种交配1次，就能最大限度地适应自己的身体。因此，在这两个物种共存的地区，多重交配可能是适宜的。对于为什么一夫多妻制经常会持续下去，尽管它会给女性带来多重代价，人们提出了许多可能的解释。一种这样的解释是避免了与基因不相容的雄性交配相关的成本。遗传不相容可以被认为是遗传上太相似(近亲繁殖)和太不相似(近亲繁殖或杂交)的个体的一种谱系。在这里，我们寻找证据表明，远缘繁殖水平影响种子害虫Lygaeus equestris的一夫多妻制的好处。我们的系统允许我们在遗传相似性的水平上测试一夫多妻制的好处，从全同胞到异种，无论是产卵还是孵化成功。我们发现，虽然近交水平似乎对种内交配的适合度没有影响，一夫多妻制似乎也不会导致生育力或繁殖力的任何增加，但与近缘物种Lygaeus Simans杂交会带来相当大的适合度成本。然而，这些成本可以通过与同种植物的一次交配来节省。因此，一夫多妻制在与密切相关物种共存并存在生殖干扰的种群中可能是有益的。然而，物种内的遗传不亲和性不太可能是该物种一夫多妻制背后的驱动力。此外，这种挽救生育能力的机制尚不清楚，因为操纵雄性角质层碳氢化合物谱(雌性可以用来评估雄性身份的一种可能机制)对雌性后代的产生没有影响。
Mating can be both costly and dangerous. Despite this, females of many species typically mate more than once and with different males. We found that female seed bugs only benefit from mating with more than 1 male if one of her mates was a different species. Females needed only 1 mating with her own species to maximize her fitness. Thus, multiple mating may be adaptive in areas where the 2 species coexist. There have been many potential explanations put forward as to why polyandry often persists despite the multiple costs it can inflict on females. One such explanation is avoidance of costs associated with mating with genetically incompatible males. Genetic incompatibility can be thought of as a spectrum from individuals that are genetically too similar (inbreeding) to those that are too dissimilar (outbreeding or hybridization). Here we look for evidence that the level of outbreeding influences the benefits of polyandry in the seed bug Lygaeus equestris. Our system allows us to test for benefits of polyandry at levels of genetic similarity ranging from full siblings to heterospecifics, both in terms of egg production and hatching success. We found that while outbreeding level appeared to have no effect on fitness for intraspecific matings, and polyandry did not appear to result in any increase in fertility or fecundity, hybridization with a closely related species, Lygaeus simulans, carried considerable fitness costs. However, these costs could be rescued with a single mating to a conspecific. Thus, polyandry may be beneficial in populations that co-occur with closely related species and where there is reproductive interference. However, within-species genetic incompatibility is unlikely to be the driving force behind polyandry in this species. Furthermore, the mechanism underlying this rescue of fertility remains unclear as manipulation of male cuticular hydrocarbon profile, a possible mechanism by which females can assess male identity, had no effect on female offspring production.