Evolution of Color Vision in a Mimetic Butterfly Complex

帝王蝶和总督蝶是最著名的防御性翅膀颜色模仿的例子，但人们对这两个物种的视觉系统知之甚少。像典型的成虫一样，君主和总督具有由紫外线(UV)、蓝色(B)和长波长(L)敏感的视觉色素调节的色觉。帝王的眼睛也有异质表达的滤色剂，这可能会扩大可见光谱中红绿部分的色觉范围。相比之下，总督的眼睛缺乏这些滤色剂，并且在光谱的同一部分是色盲，包括它们自己的橙色翅膀颜色。此外，L敏感的视觉色素的最大吸收光谱在该属蝴蝶之间也有显著的差异，总督L的色素显著蓝移。行为测试将被用来检查比较颜色视觉，总督和君主的翅膀反射数据将被收集并用于交配偏好实验。然后，将进行行为实验，以检验橙色盲人总督在选择配偶时使用紫外线反射白点作为提示的假设。此外，果蝇转基因和定点突变将从功能上评估这些蝴蝶的天然视觉色素，并使用突变的视觉色素来确定正选择下的残留物。比较的色觉和交配偏好数据将为红绿色盲蝴蝶的眼睛和颜色视觉系统的积极选择提供重要的生物学见解。该项目将为博士后助理提供一个良好的多层次综合方法的培训环境。UCI的本科生来自NSF资助的少数民族科学项目学生池，他们将被招募并接受分子生物学方面的培训。关于蝴蝶视觉和行为的讲座将被编入昆虫生理学的高级课程，并在网络上公开提供。

Monarch and viceroy butterflies are the most famous example of defensive wing color mimicry, but little is known about the visual system of either species. Like the typical adult insect, monarchs and viceroys have color vision mediated by ultraviolet (UV), blue (B) and long (L) wavelength-sensitive visual pigments. Monarch eyes also have heterogeneously-expressed filtering pigments that may extend the range of color vision in the red-green part of the visible spectrum. By contrast, viceroy eyes lack these filtering pigments and are color-blind in the same part of the spectrum, which includes their own orange wing color. In addition, there is significant variation in the absorbance spectrum maximum of the L sensitive visual pigment among this genus of butterflies, with the viceroy L pigment being significantly blue-shifted. Behavioral tests will be used to examine comparative color vision, and wing reflectance data from viceroys and monarchs will be collected and used in the context of mating preference experiments. Behavioral experiments will then be performed to test the hypothesis that the orange-blind viceroys use the UV-reflecting white spots as a cue when selecting mates. Moreover, Drosophila transgenesis and site-directed mutagenesis will functionally evaluate the native visual pigments of these butterflies and use mutant visual pigments to define residues under positive selection. Comparative color vision and mating preference data will provide important biological insights into positive selection on the eyes and color vision system of butterflies for red-green color-blindness. This project will provide an excellent training environment for a postdoctoral associate in multi-level integrated approaches. Undergraduates at UCI from the NSF-funded Minority Science Program student pool will be recruited and trained in molecular biology. Lectures on butterfly vision and behavior will be developed for an upper-division course on insect physiology and made publicly available on the web.