Department of Zoology, University of Wisconsin, Madison, WI 53706, USA.
J Evol Biol. 2012 Apr;25(4):759-69. doi: 10.1111/j.1420-9101.2012.02471.x. Epub 2012 Feb 9.
Population divergence in antipredator defence and behaviour occurs rapidly and repeatedly. Genetic differences, phenotypic plasticity or parental effects may all contribute to divergence, but the relative importance of each of these mechanisms remains unknown. We exposed juveniles to parents and predators to measure how induced changes contribute to shoaling behaviour differences between two threespine stickleback species (benthics and limnetics: Gasterosteus spp). We found that limnetics increased shoaling in response to predator attacks, whereas benthics did not alter their behaviour. Care by limnetic fathers led to increased shoaling in both limnetic and benthic offspring. Shoaling helps limnetics avoid trout and avian predation; our results suggest that this adaptive behaviour is the result of a combination of paternal effects, predator-induced plasticity and genetic differences between species. These results suggest that plasticity substantially contributes to the rapid divergence in shoaling behaviour across the post-Pleistocene radiation of sticklebacks.
种群在防御和行为上的趋异可以迅速且反复地发生。遗传差异、表型可塑性或亲本效应都可能促成趋异，但这些机制的相对重要性尚不清楚。我们让幼鱼接触亲鱼和捕食者，以衡量诱导变化如何导致两种三刺鱼（底栖和湖泊：棘鱼属）在集群行为上的差异。我们发现，湖泊型鱼在受到捕食者攻击时会增加集群，而底栖型鱼则不会改变它们的行为。湖泊型亲鱼的照顾会导致湖泊型和底栖型后代的集群行为增加。集群有助于湖泊型鱼躲避鳟鱼和鸟类捕食；我们的结果表明，这种适应性行为是亲本效应、捕食者诱导的可塑性和物种间遗传差异的综合结果。这些结果表明，可塑性在棘鱼属经历更新世后辐射过程中的集群行为快速趋异中起到了实质性的作用。
