Department of Biology, Marquette University, Milwaukee, WI, United States.
Department of Biology, University of Virginia, Charlottesville, VA, United States.
Evolution. 2024 May 1;78(5):987-994. doi: 10.1093/evolut/qpae025.
Color and pattern are often critical to survival and fitness, but we know little about their genetic architecture and heritability in groups like reptiles. We investigated the genetic architecture for the pattern of the dewlap-an extensible throat fan important for communication-in anole lizards. We studied the Hispaniolan bark anole (Anolis distichus)-a species that exhibits impressive intraspecific dewlap polymorphism across its range-by conducting multigenerational experimental crosses with 2 populations, one with a solid pale yellow dewlap and another with an orange dewlap surrounded by a yellow margin. Upon rejecting the hypothesis that the extent of the orange pattern is a quantitative trait resulting from many loci of minor effect, we used a maximum likelihood model-fitting framework to show that it is better explained as a simple Mendelian trait, with the solid yellow morph being dominant over the blush orange. The relatively simple genetic architecture underlying this important trait helps explain the complex distribution of dewlap color variation across the range of A. distichus and suggests that changes in dewlap color and pattern may evolve rapidly in response to natural selection.
颜色和图案通常对生存和适应至关重要，但我们对像爬行动物这样的群体的颜色和图案的遗传结构和遗传力知之甚少。我们研究了蜥蜴的颈垂图案（一种用于交流的可伸展喉扇）的遗传结构。我们通过对具有淡黄色颈垂的一个种群和具有橙色颈垂和黄色边缘的另一个种群进行多代实验杂交，研究了分布于伊斯帕尼奥拉岛的树皮蜥蜴（Anolis distichus）——一种在其分布范围内表现出令人印象深刻的种内颈垂多态性的物种。在拒绝橙色图案的程度是由许多微效基因座产生的数量性状的假设后，我们使用最大似然模型拟合框架表明，它更好地解释为一种简单的孟德尔性状，其中淡黄色形态对脸红橙色形态具有显性。这种重要性状背后相对简单的遗传结构有助于解释 A. distichus 分布范围内颈垂颜色变化的复杂分布，并表明颈垂颜色和图案的变化可能会迅速响应自然选择而进化。
