Evolution of Color Polymorphism Using the Hawaiian Happy Face Spider, Theridion Grallator

多态性是指在一个杂交种群中出现几种不同的不连续形式，通常涉及颜色。已经提出了许多机制来解释这种多态性的发生，但这些解释很少是结论性的。这里的建议着重于多态性在任何给定谱系的代表中经常以间歇性的方式出现的事实。这项研究的重点是夏威夷蜘蛛Theridion grallator，它展示了一个高度可见的多态性状态。为了确定：(1)为什么不同的种群表现出多态性的遗传模式；(2)观察到的磨粉虱与远亲种卵形Enoplognatha ovata的表面相似性是否具有相似的遗传机制。然后，研究将检查蜘蛛谱系中这种相似颜色多态性的分布，并评估谱系中不相关代表之间的相似性是重复的独立进化事件还是平行进化。阐明自然和应用系统中间歇性和广泛发生多态性的机制将有助于了解选择是如何运作的。

Polymorphism refers to the occurrence of several different discontinuous forms within a single interbreeding population, and frequently involves color. A number of mechanisms have been advanced to explain the occurrence of such polymorphisms, yet the explanations are seldom conclusive. The proposal here focuses on the fact that polymorphism frequently appear in an intermittent fashion among representatives of any given lineage. The study focuses on the Hawaiian spider Theridion grallator which demonstrates a highly visible state of polymorphism. The pattern of inheritance of the polymorphism in T. grallator will be examined in order to determine: (1) why different populations appear to exhibit modes of inheritance of the polymorphism; and (2) whether the observed superficial similarities between T. grallator and Enoplognatha ovata, a distantly related species, have a similar mechanism of inheritance. The study will then examine the distribution of such similar color polymorphism within the spider lineage, and assesses whether similarities among unrelated representatives of the lineage are repeated independent evolutionary events or parallel evolution. Elucidation of the mechanisms underlying the intermittent and widespread occurrence of polymorphism in both natural and applied systems will contribute to the knowledge of how selection operates.