Being a bright snake: testing aposematism and mimicry in a Neotropical forest

Based on color patterns and behavioral similarities, venomous
coral snake Micrurus corallinus (Elapidae) may act as a model for two
polymorphic species, Erythrolamprus aesculapii (Dipsadidae) and Micrurus
decoratus (Elapidae). Plasticine replicas were used to investigate the
aposematism of these coloration patterns and whether these species may be
part of mimetic complexes in two Atlantic Forest localities in South-east
Brazil. Coral replicas were more avoided when set upon a white background,
evincing that the pattern may act aposematically in contrast with light
substrates. Birds attacked all four patterns equally during the mimicry
experiments. Birds of prey, known to be effective in predating snakes, are
quite abundant in the study areas, which may have led to this lack of
avoidance. Accordingly, they predated more adult-sized replicas, which
could be more dangerous. Interestingly, opossum avoided the Micrurus
corallinus and Erythrolamprus aesculapii replicas that resembled the model.
This suggests that opportunistic predators, as the opossum may be important
selective agents in mimicry complexes.