Polarized light sensitivity in Pieris rapae is dependent on both color and intensity [RESEARCH ARTICLE]

Adam J. Blake, Gina S. Hahn, Hayley Grey, Shelby A. Kwok, Deby McIntosh, and Gerhard Gries There is an ever increasing number of arthropod taxa shown to have polarization sensitivity throughout their compound eyes. However, the downstream processing of polarized reflections from objects is not well understood. The small white butterfly, Pieris rapae, has been demonstrated to exploit foliar polarized reflections, specifically the degree of linear polarization (DoLP), to recognize host plants. The well-described visual system of P. rapae includes several photoreceptor types (red, green, blue) that are sensitive to polarized light. Yet, the roles and interaction among photoreceptors underlying the behavioral responses of P. rapae to stimuli with different DoLPs remain unknown. To investigate potential neurological mechanisms, we designed several two-choice behavioral bioassays, displaying plant images on paired LCD monitors which allowed for independent control of polarization, color and intensity. When we presented choices between stimuli that differed in either color or DoLP, both decreasing and increasing the intensity of the more attractive stimulus reduced the strength of preference. This result suggests differences in color and DoLP are perceived in a similar manner. When we offered a DoLP choice between plant images manipulated to minimize the response of blue, red, or blue and red photoreceptors, P. rapae shifted its preference for DoLP, suggesting a role for all of thes...

Source: Journal of Experimental Biology - May 26, 2020 Category: Biology Authors: Blake, A. J., Hahn, G. S., Grey, H., Kwok, S. A., McIntosh, D., Gries, G. Tags: RESEARCH ARTICLE Source Type: research