Vanoverbeke J
Laboratory of Aquatic Ecology, Katholieke Universiteit Leuven, Belgium.
Proc Biol Sci. 1999 Dec 22;266(1437):2471-7. doi: 10.1098/rspb.1999.0948.
Cyclical parthenogenesis involves an alternation of parthenogenetic and sexual reproduction. In cyclical parthenogens with a short generation time, seasonal succession of clones switching to sexual reproduction at different periods of the growing season entails the risk of severe inbreeding with associated fitness costs. We show, however, that differences in genotype frequencies between males and sexual females result in a substantial reduction in the probability of selfing in natural Daphnia populations. This suggests that responses to male- and sexual egg-inducing stimuli may be uncoupled at the level of individual clones as a mechanism to avoid severe inbreeding.
周期性孤雌生殖涉及孤雌生殖和有性生殖的交替。在世代时间较短的周期性孤雌生殖生物中，在生长季节的不同时期，克隆个体季节性地转变为有性生殖，这带来了严重近交并伴有适合度代价的风险。然而，我们发现，雄性和有性生殖雌性之间的基因型频率差异，会使自然条件下的水蚤种群中自体受精的概率大幅降低。这表明，作为一种避免严重近交的机制，对雄性诱导刺激和有性卵诱导刺激的反应在个体克隆水平上可能是解耦的。
