Modeling evolution of firefly-like signal vocabularies

Fireflies communicate by producing bioluminescence to signal their presence and court mates. In particular, some species emit patterns of short flashes with the potential to encode information; males flash according to a species-specific pattern in order to attract and locate females. Multiple firefly species with different characteristic patterns can share the same habitat, leading to visual clutter that could potentially hinder successful communication among conspecifics. We investigate how flash sequences can co-evolve to be distinguishable by developing a "vocabulary generator" model. We use this model to simulate sequences that minimize both their mutual similarity with each other and their individual predation risks. We observe an emergent periodicity in the resulting optimal sequences despite the lack of any constraints on the sequences to be periodic. We also demonstrate a method of reconstructing potential cost functions from the phylogenetic relationships of extant species alongside their characteristic flash patterns.