Aposematic Coloration in Adults and Larvae of Lygaeus equestris and Its Bearing on Müllerian Mimicry: An Experimental Study on Predation on Living Bugs by the Great Tit Parus major@@@Aposematic Coloration in Adults and Larvae of Lygaeus equestris and Its Bearing on Mullerian Mimicry: An Experimental Study on Predation on Living Bugs by the Great Tit Parus major

It is generally held that aposematic forms gain mutual protection from predation as long as they share "some striking feature", e.g. a red-and-black or yellow-and-black colour pattern. To test whether a bird generalizes between adults and larvae of Lygaeus equestris (both instars coloured red-and-black), 18 great tits Parus major were offered either adults or larvae in four consecutive trials, and the opposite instar in four subsequent trials. The bugs were attacked in 45% of the trials but only two were completely consumed. Sixty-nine percent of the adults and 33% of the larvae survived an attack. The number of attacks increased between trials 4 and 5, and birds attacked the second presented instar as fast and as frequently as the instar first presented. However, although similar proportions of adults and larvae were attacked during trials 1-4 and 5-8, overall mortality was lower during the last set of trials, but only significantly so for the larvae (Larvae: p = 0.028; Adults: p = 0.261). Thus, we conclude that it does not suffice for two mullerian mimics, or two aposematic forms, to possess "some striking feature" in common to gain mutual protection from predation. On the contrary our results indicate that two aposematic forms must be very similar to gain full mutual protection and thus then add to the understanding of the reason for the close resemblance so commonly encountered not only between batesian mimics and their aposematic models but also between millerian mimics.