Data from: Adaptive plasticity and genetic divergence in feeding efficiency during parallel adaptive radiation of whitefish (Coregonus spp.)

Parallel phenotypic divergence in replicated adaptive radiations could either result from parallel genetic divergence in response to similar divergent selection regimes, or from equivalent phenotypically plastic response to the repeated occurrence of contrasting environments. In postglacial fish replicated divergence in phenotypes along the benthic-limnetic habitat axis is commonly observed. Here we use two benthic-limnetic species pairs of whitefish from two Swiss lakes, raised in a common garden design, with reciprocal food treatments in one species pair, to experimentally measure whether feeding efficiency on benthic prey has a genetic basis or whether it underlies phenotypic plasticity (or both). To do so we offered experimental fish mosquito larvae, partially burried in sand, and measured multiple feeding efficiency variables. Our results reveal both, genetic divergence as well as phenotypically plastic divergence in feeding efficiency, with the phenotypically benthic species raised on benthic food being the most efficient forager on benthic prey. This indicates that both, divergent natural selection on genetically heritable traits and adaptive phenotypic plasticity, are likely important mechanisms driving phenotypic divergence in adaptive radiation.重复适应性辐射（replicated adaptive radiations）中发生的平行表型分化，既可源于相似歧化选择机制（divergent selection regimes）下的平行遗传分化，也可由对反复出现的异质环境产生的等效表型可塑性（phenotypic plasticity）响应所导致。在冰期后鱼类类群中，沿底栖-浮游生境轴出现的重复表型分化现象较为普遍。本研究选取来自两个瑞士湖泊的两组白鱼底栖-浮游物种对，采用共同花园实验设计（common garden design），其中一组物种对还设置了交叉食物处理方案，以此实验探究底栖猎物的摄食效率是否具有遗传基础、或受表型可塑性调控（或两者兼具）。为此，我们向实验个体投喂部分埋于沙中的蚊幼虫，并测定了多项摄食效率相关指标。研究结果同时揭示了摄食效率的遗传分化与表型可塑性分化，其中以底栖食物饲养的底栖表型物种，在底栖猎物的觅食效率上表现最优。这表明，针对可遗传性状的歧化自然选择与适应性表型可塑性，均可能是推动适应性辐射中表型分化的关键机制。