Meeting Abstract

7.5  Monday, Jan. 4  Characterizing the pattern of opsin gene expression in the retina: insight into how guppies (Poecilia reticulata) see their mate’s true colors. WINDSOR , DJ*; OWENS, GL; ALLISON, WT; TAYLOR, JS; University of Victoria ; University of Victoria ; University of Alberta ; University of Victoria dianawin@uvic.ca

Phenotypically guppies (Poecilia reticulata) display sexual dimorphism with regard to size and coloration, with males having a particularly colorful and polymorphic pattern. Interestingly, guppies also have one of the largest opsin gene repertoires yet described. This opsin repertoire includes one SWS1 gene, two SWS2 genes (A&B), four LWS genes (S180, A180, P180, S180r), one RH1 gene, and two RH2 genes (1&2). This expanded repertoire may allow for enhanced wavelength discrimination ability and/or precise tuning to the photic environment. Therefore guppies may look even more colorful to one another than they do to human observers. However, this all depends upon whether these genes are expressed in the retina at the same time and on the relative positions of cone cells expressing these different opsins. In order to investigate this we used in situ hybridization to determine when and where guppy opsin genes are expressed. This was undertaken in both males and females in order to determine whether sexually dimorphic expression was present. Understanding the color discriminatory ability of the guppy is pivotal to comprehending male color based sexual selection, a trait exhibited throughout the animal kingdom.