Rand M S
Department of Environmental, Population, and Organismic Biology, University of Colorado, Boulder 80309-0334.
Gen Comp Endocrinol. 1992 Dec;88(3):461-8. doi: 10.1016/0016-6480(92)90241-b.
This study investigated the influence of sex steroids on the expression of seasonally labile and sexually dimorphic coloration in the red-lipped plateau lizard. The responses of ventral blue and polymorphic facial coloration to exogenous steroid administration were assessed. Though facial color is usually dimorphic in nature, males and females did not differ in the degree to which they expressed facial coloration following administration of testosterone (T). Both sexes developed significantly more ventral blue coloration than controls, but a fundamental dimorphism in intensity, favoring males, was maintained throughout the experiment. These results indicate that facial coloration is under activational influence of T. The ventral blue coloration is probably organized at sexual maturation, thus manifesting the more vivid expression in males. Males of this subspecies are polymorphic for facial coloration. Administration of T did not cause any lizards to change hue, whether their color morph was yellow or orange or lacked the facial pigments altogether. The difference among color morphs is probably not controlled by differences in circulating steroid concentrations and is hypothesized to be under genetic control.
本研究调查了性类固醇对红唇高原蜥蜴季节性不稳定和两性异形体色表达的影响。评估了腹部蓝色和多态性面部颜色对外源类固醇给药的反应。尽管面部颜色在本质上通常是两性异形的，但在给予睾酮（T）后，雄性和雌性在表达面部颜色的程度上并无差异。两性的腹部蓝色均比对照组显著增多，但在整个实验过程中，强度上的基本两性异形现象依然存在，雄性更为明显。这些结果表明，面部颜色受T的激活作用影响。腹部蓝色可能在性成熟时形成，因此在雄性中表现得更为鲜艳。该亚种的雄性面部颜色具有多态性。给予T并未使任何蜥蜴改变体色，无论其颜色形态是黄色、橙色还是完全缺乏面部色素。颜色形态之间的差异可能不受循环类固醇浓度差异的控制，据推测是受基因控制。
