Dissertation Research: Selection on Wing Coloration

1928年，汉密尔顿·达尔文提出“性选择”来解释各种各样的特征，这些特征都具有明显不利于生存的矛盾性质。他提出，这些特征已经进化，因为它们在竞争或吸引配偶时给携带者带来了优势。性选择现在被广泛认为是两性差异进化的主要机制，也是新物种进化的潜在重要因素。然而，人们对性选择背后的机制、限制性选择的因素以及性选择特征变异的本质所知甚少。格雷戈里·f·格雷瑟（Gregory F. Grether）的博士论文研究将在一种无脊椎动物系统模型——红宝石斑豆蛉（rubyspot damselfly）中解决其中的几个问题。格雷瑟先生已经获得了证据，证明雄性翅膀底部的红色斑点是性选择的。他现在将进行一系列的实验来(1)确定翅膀斑点的变化对雄性之间相互作用的影响，(2)测试雌性配偶偏好，(3)根据对捕食者和猎物的显著性来衡量翅膀斑点的生态成本，以及(4)研究翅膀斑点变化与雄性质量之间的关系，通过偏离双边不对称来评估。格雷瑟先生对性选择理论有着深刻的理解，并开发了一个实验系统，有可能为该理论的测试产生明确的结果。

9311928 Hamilton Darwin offered "sexual selection" as an explanation for a wide variety of traits having in common the paradoxical quality of being apparently detrimental to survival. He proposed that such traits have evolved because they give an advantage to the bearer in competing for or attracting mates. Sexual selection is now widely regarded to be a major mechanism for the evolution of differences between the sexes and a potentially important factor in the evolution of new species. Yet little is known about the mechanisms underlying sexual selection, the factors constraining it, or the nature of variation in sexually selected traits. Mr. Gregory F. Grether's doctoral-dissertation research will address several of these issues in a model invertebrate system, the rubyspot damselfly. Mr. Grether has obtained evidence that the red-pigmented spots at the base of the males' wings are sexually selected. He now will conduct a series of experiments to (1) determine the effect of wing-spot variation on interactions between males, (2) test for female mate preferences, (3) measure ecological costs of the wing spot in terms of conspicuousness to predators and prey, and (4) investigate the relationship between wing-spot variation and male quality as assessed by deviations from bilateral asymmetry. Mr. Grether has demonstrated outstanding depth of understanding of sexual-selection theory and has developed an experimental system with the potential to produce unequivocal results for tests of the theory.