Summary: Moosman et al. (2009)

Animal signals evolve in a variety of contexts. Some male fireflies (Coleoptera: Lampyridae) produce bioluminescent courtship signals during mate searching, and these males are often chemically defended. These courtship signals may have consequences (positive/negative) that are unrelated to mating. Moosman et al. (2009) examined whether Photinus flash signals are aposematic signals for insectivorous bats. They observed four species of North American bats in the field, then conducted behavioural and diet experiments in the laboratory to assess taste responses to the fireflies. Interestingly, fireflies were not found in bat faeces, even though they co-occurred in the field. Bats found the taste of meal worms coated with homogenized fireflies aversive, but responded differentially to moving lures based on a combination of lure size and flash cues. Moosman et al. (2009) suggest that flash signals of Photinus fireflies probably act as aposematic warnings to the common bat Eptesicus fuscus. This indicates that bioluminescent courtship signalling in fireflies may operate under competing selective pressures.