Rosengrave Patrice, Montgomerie Robert, Gemmell Neil
Department of Anatomy, University of Otago, Dunedin, New Zealand Allan Wilson Centre for Molecular Ecology and Evolution, Department of Anatomy University of Otago, Dunedin, New Zealand
Department of Biology, Queen's University, Kingston, Ontario, Canada K7 L 3N6.
Proc Biol Sci. 2016 Mar 30;283(1827):20160001. doi: 10.1098/rspb.2016.0001.
In this study, we investigated two potentially important intersexual postcopulatory gametic interactions in a population of chinook salmon (Oncorhynchus tshawytscha): (i) the effect of female ovarian fluid (OF) on the behaviour of spermatozoa during fertilization and (ii) the effects of multilocus heterozygosity (MLH) (as an index of male quality) and female-male genetic relatedness on sperm behaviour and male fertilization success when there is sperm competition in the presence of that OF. To do this, we conducted a series of in vitro competitive fertilization experiments and found that, when ejaculates from two males are competing for access to a single female's unfertilized eggs, fertilization success was significantly biased towards the male whose sperm swam fastest in the female's OF. Embryo survival--a measure of fitness--was also positively correlated with both sperm swimming speed in OF and male MLH, providing novel evidence that cryptic female choice is adaptive for the female, enhancing the early survival of her offspring and potentially influencing her fitness.
在本研究中，我们调查了奇努克鲑（Oncorhynchus tshawytscha）种群中两种潜在重要的两性交配后配子间相互作用：（i）雌性卵巢液（OF）对受精过程中精子行为的影响；（ii）在存在OF的情况下发生精子竞争时，多基因座杂合性（MLH）（作为雄性质量的指标）以及雌雄遗传相关性对精子行为和雄性受精成功率的影响。为此，我们进行了一系列体外竞争性受精实验，发现当来自两个雄性的射精竞争获取单个雌性未受精卵的机会时，受精成功率显著偏向于其精子在雌性OF中游动速度最快的雄性。胚胎存活率——一种适合度指标——也与精子在OF中的游动速度和雄性MLH均呈正相关，这提供了新的证据，表明隐性雌性选择对雌性具有适应性，可提高其后代的早期存活率，并可能影响其适合度。
