Hansson Truls H, Fischer Barbara, Mazzarella Anna B, Voje Kjetil L, Vøllestad Leif Asbjørn
Department of Biosciences Centre for Ecological and Evolutionary Synthesis University of Oslo PO Box 1066 Blindern N-0316 Oslo Norway.
Department of Biosciences Centre for Ecological and Evolutionary Synthesis University of Oslo PO Box 1066 Blindern N-0316 Oslo Norway; Department of Theoretical Biology University of Vienna Althanstrasse 141090 Vienna Austria; Konrad Lorenz Institute for Evolution and Cognition Research Martinstrasse 12A-3400 Klosterneuburg Austria.
Ecol Evol. 2016 Apr 6;6(10):3154-60. doi: 10.1002/ece3.2020. eCollection 2016 May.
In the threespine stickleback Gasterosteus aculeatus model system, phenotypes are often classified into three morphs according to lateral plate number. Morph identity has been shown to be largely genetically determined, but substantial within-morph variation in plate number exists. In this study, we test whether plate number has a plastic component in response to salinity in the low-plated morph using a split-clutch experiment where families were split in two, one half raised in water at 0 and the other at 30 ppt salt. We find a small salinity-induced plastic effect on plate number in an unexpected direction, opposite to what we predicted: Fish raised in freshwater on average have slightly more plates than fish raised in saltwater. Our results confirm that heritability of plate number is high. Additionally, we find that variance in plate number at the family level can be predicted from other family level traits, which might indicate that epistatic interactions play a role in creating the observed pattern of lateral plate number variation.
在三刺鱼（Gasterosteus aculeatus）模型系统中，表型通常根据侧板数量分为三种形态。形态特征已被证明在很大程度上由基因决定，但形态内的板数存在显著差异。在本研究中，我们通过一个分窝实验来测试低板形态的三刺鱼的板数是否会因盐度而产生可塑性变化，即将鱼家族分成两半，一半在盐度为0的水中饲养，另一半在盐度为30ppt的水中饲养。我们发现盐度对板数产生了一个小的可塑性影响，但其方向出乎意料，与我们的预测相反：在淡水中饲养的鱼平均比在盐水中饲养的鱼的板数略多。我们的结果证实板数的遗传力很高。此外，我们发现家族水平的板数方差可以从其他家族水平的特征中预测出来，这可能表明上位性相互作用在形成观察到的侧板数变异模式中起作用。
