Data from: An experimental test of the effect of predation upon behaviour and trait correlations in threespine stickleback

Benthic and limnetic threespine stickleback (Gasterosteus aculeatus) are a classic example of ecological speciation. Behavioural and armour divergence between these species has been predicted to be the result of divergent selection driven in part by differential predation from cutthroat trout (Oncorhynchus clarki). To experimentally test this prediction, we reared split families of benthic-limnetic hybrids in the presence or absence of trout predation. Our results show that the presence of trout had little effect upon stickleback behaviour. We then compared performance in behavioural assays among stickleback that varied in armour to test if armour morphology correlates with behaviour. Our measurements revealed trait correlations between several behaviours and components of armour morphology. Trout predation did not result in an increased correlation between traits, therefore differential trout predation between benthics and limnetics is unlikely to be the cause of these correlations. The presence of trait correlations in advanced generation hybrids suggests that pleiotropy or linkage between genes underlying behaviour and armour morphology may be greater than previously appreciated.

底栖与浮游型三棘刺鱼（Gasterosteus aculeatus）是生态物种形成的经典范例。这类物种间的行为与盔甲形态分化，被推测部分源于斑首割喉鳟（Oncorhynchus clarki）的差异化捕食所驱动的歧化选择。为实验验证这一预测，我们将底栖-浮游型杂交分离家系分别置于有、无割喉鳟捕食压力的环境中饲养。实验结果显示，割喉鳟的存在对刺鱼的行为几乎无显著影响。随后，我们针对盔甲形态存在差异的刺鱼开展行为测定，以检验盔甲形态与行为性状是否存在相关性。测量结果表明，多项行为性状与盔甲形态的多个组分之间存在显著关联。割喉鳟捕食并未增强这类性状间的相关性，因此底栖与浮游型刺鱼间的差异化捕食压力，不太可能是上述性状关联的成因。在多代杂交后代中检测到的性状关联，提示调控行为与盔甲形态的相关基因之间，其多效性或遗传连锁程度可能远超此前的认知。