Presenter: Kyri Forman
Authors: Kyri Forman, Craig Thulin
Faculty Advisor: Heath Ogden
Institution: Utah Valley University
Within the monarch butterfly (Danaus plexippus), an orange filtering pigment is found in the eyes and is used to discriminate between orange and yellow. It is believed this is used for deciphering between wing hues in mate selection as well as foraging for nectar (Blackiston et al., 2011 ). However, it is unknown whether or not there is a connection between this dark orange filtering pigment and the pigments in the wings of the monarch. For this study, high-pressure liquid chromatography (HPLC) and Thin Layer Chromatography (TLC) were used to compare quantities of pigment in the wings and eyes of white monarchs (Danaus plexippus nivosus) to typical orange monarchs. Pigments were extracted from whole eyes and wing fragments using acidified methanol (100% methanol with 1% HCl). White monarchs were found to have no traceable orange pigments within the wings or eyes and appear to have a significant decrease in black pigmentation in the eyes, possibly causing the unusual eye color. Within orange monarchs, two orange pigments were found in both the wings and eyes, along with traces of two black pigments, one found only in the eyes. The lack of any found orange pigment within the eyes of white monarchs signifies possible color blindness within this type. This is supported by previous reports of these butterflies being less likely to breed and forage for nectar. Future behavioral studies would be advisable to further confirm color blindness in the white monarch. It also should be noted that the orange pigments in the eyes are the same in the wings, signifying a possible connection between eye pigmentation and wing pigmentation, possibly leading to future studies on the usage of pigments as well.