Abstracts (first author)
The cichlid and reef fish visual system as a model for speciation processes
Freshwater cichlid and marine reef fish species represent spectacular products of adaptive radiations. Their amazing color diversities and well-adapted visual systems make them ideal candidates for a comparative study of molecular mechanisms involved in speciation based on the visual system. These will help to identify external factors and environmental conditions that shape color morphs and visual sensitivities. The major aims of this study are to compare (1) the coloration, (2) the molecular basis of the diversity of visual pigments, (3) visual pigment expression patterns, (4) transmission properties of the ocular media and (5) photic properties of habitats between cichlids and reef fish. Up to now, we sampled a representative set of shallow-water labrids (Labridae), damselfish (Pomacentridae) and cichlids (Cichlidae) in definite light habitats and studied their visual sensitivities composed of opsin gene variations and opsin gene expression patterns. Spectrophotometry was used to define the different light environments. To determine the molecular basis of visual pigments, we sequenced opsin genes using DNA and next generating sequencing. To quantify the relative amount of opsin gene expression we performed real time quantitative PCR.