Kim Yong-Kyu, Weber Mary Beth, Anderson Wyatt W, Gowaty Patricia Adair
Department of Genetics, University of Georgia, Athens, Georgia, USA.
Integr Zool. 2010 Sep;5(3):198-207. doi: 10.1111/j.1749-4877.2010.00205.x.
The good genes hypothesis states that choosers prefer individuals of high intrinsic quality to individuals of lower intrinsic quality. Variation in longevity is thought to reflect, in part, intrinsic quality differences of individuals in addition to the costs of mating and reproduction. Here we report longevity variation of Drosophila pseudoobscura, a species in which previous experiments have demonstrated that individual mate preferences (pre-touching mate assessments) of females and males are associated with enhanced numbers of eclosed (adult) offspring and higher egg-to-adult survival (offspring viability). Using mate assessment arenas and protocols similar to those in a previous experiment that demonstrated fitness benefits to breeders and their offspring of mating with individuals they preferred, we tested the following predictions: (i) preferred discriminatees live longer than non-preferred discriminatees; (ii) males live longer than females; and (iii) virgins live longer than mated individuals. The experiment yielded 938 individuals for longevity analysis. Sex and mating status affected longevity: males lived longer than females, virgin females lived longer than mated females, but there were no differences in longevity for mated and virgin males. Non-preferred discriminatees of both sexes survived as long as preferred discriminatees, a result inconsistent with the prediction of the good genes hypothesis for mate preferences. To our knowledge, this is the first demonstration of the cost of reproduction for females in D. pseudoobscura and of longevity variation of preferred and non-preferred discriminatees.
优良基因假说认为，选择者更喜欢内在品质高的个体，而非内在品质低的个体。寿命差异被认为部分反映了个体的内在品质差异，此外还包括交配和繁殖的成本。在此，我们报告了拟暗果蝇的寿命差异，在之前的实验中已证明，该物种中雌性和雄性的个体配偶偏好（交配前配偶评估）与羽化（成年）后代数量增加以及更高的卵到成虫存活率（后代活力）相关。我们使用与之前一项实验类似的配偶评估场地和方案，该实验证明与偏好的个体交配会给繁殖者及其后代带来适应性益处，我们检验了以下预测：（i）被偏好的被选择者比未被偏好的被选择者寿命更长；（ii）雄性比雌性寿命长；（iii）未交配个体比已交配个体寿命长。该实验产生了938个个体用于寿命分析。性别和交配状态影响寿命：雄性比雌性寿命长，未交配的雌性比已交配的雌性寿命长，但已交配和未交配的雄性在寿命上没有差异。两性中未被偏好的被选择者与被偏好的被选择者存活时间一样长，这一结果与优良基因假说中关于配偶偏好的预测不一致。据我们所知，这是首次证明拟暗果蝇雌性的繁殖成本以及被偏好和未被偏好的被选择者的寿命差异。
