Garant D, Dodson J J, Bernatchez L
Université Laval, Département de Biologie, Ste-Foy, Quebec, Canada.
J Hered. 2001 Mar-Apr;92(2):137-45. doi: 10.1093/jhered/92.2.137.
The primary objective of this study was to use highly polymorphic microsatellite loci to estimate individual reproductive success in Atlantic salmon based on the number of surviving juveniles (young of the year) at the population level under natural conditions. We inferred reproductive strategies adopted by both sexes by applying a maximum likelihood method to determine parent-offspring genotype relationships. A high degree of variance in individual reproductive success for both males and females was revealed. The high number of mates used by both sexes is not concordant with previous behavioral studies proposing that females are mainly monogamous in this species. We found little evidence supporting the prediction from previous reports of a positive relationship between individual size and realized reproductive success for either males or females. For both sexes, however, there was a significant correlation between the number of mates and the number of offspring. These results indicate that this species' mating system is more flexible than previously thought and suggest that factors such as potential genetic benefits or environmental uncertainty may also be driving the evolution and the plasticity of mating systems in Atlantic salmon.
本研究的主要目的是利用高度多态的微卫星位点，在自然条件下的种群水平上，根据存活幼鱼（当年幼鱼）的数量来估计大西洋鲑个体的繁殖成功率。我们通过应用最大似然法来确定亲子基因型关系，从而推断出两性所采用的繁殖策略。结果显示，雄性和雌性个体的繁殖成功率都存在高度差异。两性所拥有的配偶数量之多，与之前的行为学研究结果不一致，此前的研究认为该物种中雌性主要实行一夫一妻制。我们几乎没有找到证据支持先前报告中关于个体大小与雄性或雌性实际繁殖成功率之间存在正相关关系的预测。然而，对于两性而言，配偶数量与后代数量之间存在显著相关性。这些结果表明，该物种的交配系统比之前认为的更加灵活，这表明诸如潜在的遗传益处或环境不确定性等因素，也可能推动了大西洋鲑交配系统的进化和可塑性。
