The evolution of Batesian mimicry in Camponotus lateralis

The term mimicry means the imitation of characteristics of one species (i.e., the model) by another (i.e., the mimic). Since Darwins lifetimes the evolution of mimicry is of central interest for the theory of natural selection. Many insect and spider species exhibit ant mimicry, which is the imitation of ants in terms of shape or color. Hence, predators consider them to be ants and, consequently, avoid them. There are only few examples in which ants are mimicking other ant species. The Mediterranean red carpenter-ant Camponotus lateralis is considered to mimic cocktail ants (Crematogaster scutellaris). Both ant species are very similar in color although they are not closely related to each other. Since they often use shared ant-trails, even experts have confused them. The mimicry of the red carpenter-ants was vaguely postulated in the 19th century, however, until today there is no sufficient experimental evidence for corresponding hypotheses. In this multidisciplinary study, eight predictions in relation to mimicry of the red carpenter-ant should be tested experimentally. In my preliminary tests, a lizard ate red and black carpenter-ants at first equally often. However, after experience with the inedible cocktail ants, the lizard ate black carpenter ants statistically more often than red ones. This is an indication for an evolutionary advantage of the mimicry. Moreover, my observations suggest that red carpenter-ants mimic at the Apennine Peninsula another cocktail ant species than at the Balkan Peninsula. This hypothesis should be tested objectively using spectrometric measurements. Also feeding experiments with lizards will be repeated with an appropriate high number of replicas to test if the mimicry ensures an evolutionary advantage. The experimental design even allows testing a possible advantage of color variants of the red carpenter-ant at the Apennine and the Balkan Peninsula. Moreover, also a possible disadvantage for the cocktail ants, caused by mimicry, can be tested. The disadvantage for the cocktail ants is expected due to signal dilution caused by mimicry. Molecular-genetic methods should show if red carpenter-ants prefer mating with individuals from the same color variant. By doing so, the production of intermediates not mimicking a specific cocktail ant species could be avoided. Furthermore, a phylogeny of the carpenter-ants and the cocktail ants should be reconstructed to test predictions of the evolutionary sequence of the acquisition of trail-sharing behavior, red color, and speciation. This detailed investigation of mimicry in ants will provide novel findings for zoologists worldwide and will have important implications for the field of evolutionary biology.