Department of Biology, Colorado State University, Fort Collins, CO 80523, USA.
J Exp Biol. 2013 Aug 15;216(Pt 16):3132-42. doi: 10.1242/jeb.081349. Epub 2013 Apr 25.
Fish and other aquatic vertebrates use their mechanosensory lateral line to detect objects and motion in their immediate environment. Differences in lateral line morphology have been extensively characterized among species; however, intraspecific variation remains largely unexplored. In addition, little is known about how environmental factors modify development of lateral line morphology. Predation is one environmental factor that can act both as a selective pressure causing genetic differences between populations, and as a cue during development to induce plastic changes. Here, we test whether variation in the risk of predation within and among populations of Trinidadian guppies (Poecilia reticulata) influences lateral line morphology. We compared neuromast arrangement in wild-caught guppies from distinct high- and low-predation population pairs to examine patterns associated with differences in predation pressure. To distinguish genetic and environmental influences, we compared neuromast arrangement in guppies from different source populations reared with and without exposure to predator chemical cues. We found that the distribution of neuromasts across the body varies between populations based on both genetic and environmental factors. To the best of our knowledge, this study is the first to demonstrate variation in lateral line morphology based on environmental exposure to an ecologically relevant stimulus.
鱼类和其他水生脊椎动物利用其机械感受侧线来探测其周围环境中的物体和运动。侧线形态的差异在物种间得到了广泛的描述；然而，种内变异在很大程度上仍未得到探索。此外，人们对环境因素如何改变侧线形态的发育知之甚少。捕食是一种环境因素，它既能作为种群间遗传差异的选择压力，又能作为发育过程中的一种暗示，诱导可塑性变化。在这里，我们测试特立尼达孔雀鱼（Poecilia reticulata）种群内和种群间捕食风险的变化是否会影响侧线形态。我们比较了来自不同高、低捕食压力种群对的野生捕获孔雀鱼的神经丘排列，以研究与捕食压力差异相关的模式。为了区分遗传和环境的影响，我们比较了在有和没有暴露于捕食者化学信号的情况下饲养的来自不同来源种群的孔雀鱼的神经丘排列。我们发现，神经丘在身体上的分布因遗传和环境因素的不同而在种群之间有所不同。据我们所知，这项研究首次证明了基于对生态相关刺激的环境暴露的侧线形态的变异。
