Predator-based selection and the impact of edge sympatry on components of coral snake mimicry

Mimicry is a vivid example of how predator-driven selection can impact
phenotypic diversity, which itself can be influenced by the presence
(sympatry) or absence (allopatry) of a dangerous model. However, the
impact of sympatry and allopatry on predation on mimicry systems at fine
spatial scales (e.g., edge sympatry, allopatry) is not well understood. We
used a clay model study in a montane tropical site in Honduras to test the
impact of edge sympatry on 1) overall attack rates, 2) the fitness benefit
of mimetic coloration, 3) predation on specific mimetic signal components,
and 4) temporal variation in predator-based selection on mimicry
components. Unlike previous research, we found that mimetic phenotypes
received significantly more attacks than cryptic replicas in edge
sympatry, suggesting that mimetic phenotypes might not confer a fitness
benefit in areas of edge sympatry. Additionally, we documented temporal
variation in predator-based selection, as the impacts of allopatry on
predatory attacks varied among years. Our results imply that the effect of
sympatry and allopatry on predator-based selection in mimicry systems may
be more complex than previously thought for species-rich assemblies of
coral snakes and their mimics in the montane tropics.