Escalated disputes in Calopteryx maculata and the role of asymmetry assessment.

In line with ESS theory, natural selection favors accurate assessment of relative role in competitive interactions that escalate. Escalations are costly and dangerous but are worthwhile if they add to an individual's fitness directly (through success) or indirectly (gain of information). We examined asymmetries in resource holding potential (measured by wing size, abdomen length, and mass) in a population of C. maculata. We compared morphological data with behavioral data on pairs of individuals that had potential ""face-off"" assessment phases and either escalated or did not escalate. Males that had low levels of size asymmetry escaled their contests more often than males that had high levels of size asymmetry (Wilks' Lambda: 0.920839, F (1,37) = 0.2434, P < 0.011). Size asymmetry was concluded to be one of many potential factors in C. maculata assessment.http://deepblue.lib.umich.edu/bitstream/2027.42/55035/1/3477.pdfDescription of 3477.pdf : Access restricted to on-site users at the U-M Biological Station