Coloration indicates body size in Calopteryx maculata (Odonata: Calopterygidae)


Calopteryx maculata has become a model system for studying behaviour and reproduction in odonates. Its iridescent coloration is thought to be important in intraspecific interactions but no study has yet measured coloration in a quantitative manner. In a recent study, Fitzstephens & Getty (2000. Animal Behaviour 60: 851-855) showed that lipld levels predict coloration as determined by Munsell chips, such that fat males were blue and lean males were green. In this study we quantified color in C. maculata with a spectrometer to test the prediction of Fitzstephens & Getty (2000) using quantitative measures. We found that body size, but not lipid levels, correlates with color. In our study, larger males were green and smaller males blue. Territorial males did not differ from non-territorial males in color, size, or lipid levels. Coloration thus predicts size in male C. maculata, but the significance of this in intraspecific interactions remains unclear.

Issue section: Article