Evidence for visual evasion of arctiid moth predators: the influence of conspicuous coloration patterns on predation in Utetheisa ornatrix caterpillar models

Resumo

In nature, organisms have developed various defense mechanisms against predation. Aposematism, in which animals display conspicuous coloration combined with a defense mechanism to deter predation, is one of the primary defensive strategies studied. Conspicuous color patterns have been the focus of intense and justified attention by biologists since the time of Charles Darwin. Many unpalatable species, especially among insects, exhibit conspicuous coloration. However, by evolving conspicuous coloration similar to that of an unpalatable species, palatable animals can also gain an evasive advantage through mimicry, without the need to develop a real defense. In Utetheisa ornatrix, coloration manifests in different patterns, including black, yellow, and white, and is considered conspicuous and aposematic for some species. This study evaluated the influence of conspicuous coloration on predation in U. ornatrix larval models, testing two hypotheses: first, that models with conspicuous coloration are less predated than cryptic or non-conspicuous models; second, that models with a fully developed conspicuous pattern are less predated than those with intermediate patterns or purely black coloration. The results indicate that among the tested conspicuous coloration models, predators avoided the pattern most similar to U. ornatrix and the cryptic pattern, showing a preference for the non-conspicuous pattern. Additionally, among the conspicuous patterns, the black-and-white and fully developed patterns were less predated than the black-yellow and purely black patterns, with the latter being the most predated.