Adaptive Color Polymorphism and Unusually High Local Genetic Diversity in the Side-Blotched Lizard, Uta stansburiana
Adaptive Color Polymorphism and Unusually High Local Genetic Diversity in the Side-Blotched Lizard, Uta stansburiana
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DOI：
10.1371/journal.pone.0047694
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发表时间：
2012-10-25
期刊：
影响因子：
3.7
通讯作者：
Routman, Eric J.
中科院分区：
文献类型：
--
作者：
Micheletti, Steven;Parra, Eliseo;Routman, Eric J.
最近，适应性颜色变化的研究已经成为检验自然选择遗传学的流行模型。我们研究了一个侧面斑点蜥蜴（Uta stansburiana）种群的颜色模式多态性和遗传变异，该种群生活在深色（熔岩）和浅色（花岗岩）基质的栖息地。我们在实验室条件下对成人表型可塑性进行了有限的实验。我们在野外记录了基质和蜥蜴的颜色模式，以确定蜥蜴是否倾向于与基质相匹配。最后，我们检查了一个基因（黑素皮质素1受体）的遗传变异，该基因已被证明会影响其他物种蜥蜴的颜色，以及一个可能是中性的基因（线粒体细胞色素b）。在熔岩流附近的地区以及从较远的地点采集了种群样本，以检查种群结构的作用。我们的俘虏Uta没有改变颜色来匹配他们的背景。我们发现，侧斑蜥蜴倾向于与在野外捕获的底物相匹配，并且黑素皮质素1受体基因的变异与该种群的颜色模式没有很好的关联。也许最引人注目的结果是，在等位基因数量方面，这个侧斑蜥蜴种群在两个遗传标记上都表现出极高的变异水平，而等位基因序列之间的变异水平相对较低。这个小区域的遗传变异与世界各地收集的远洋鱼类样本一样大，甚至更大。遗传变异的统计分析表明，快速的种群扩张可能是造成高水平变异的原因。
Recently, studies of adaptive color variation have become popular as models for examining the genetics of natural selection. We examined color pattern polymorphism and genetic variation in a population of side-blotched lizards (Uta stansburiana) that is found in habitats with both dark (lava) and light colored (granite) substrates. We conducted a limited experiment for adult phenotypic plasticity in laboratory conditions. We recorded both substrate and lizard color patterns in the field to determine whether lizards tended to match their substrate. Finally we examined genetic variation in a gene (melanocortin 1 receptor) that has been shown to affect lizard color in other species and in a presumably neutral gene (mitochondrial cytochrome b). Populations were sampled in the immediate area of the lava flows as well as from a more distant site to examine the role of population structure. Our captive Uta did not change color to match their background. We show that side-blotched lizards tend to match the substrate on which it was caught in the field and that variation in the melanocortin 1 receptor gene does not correlate well with color pattern in this population. Perhaps the most remarkable result is that this population of side-blotched lizards shows extremely high levels of variation at both genetic markers, in the sense of allele numbers, with relatively low levels of between-allele sequence variation. Genetic variation across this small region was as great or greater than that seen in samples of pelagic fish species collected worldwide. Statistical analysis of genetic variation suggests rapid population expansion may be responsible for the high levels of variation.