Abstract
Bioluminescence is found across life and has many functions. Yet we understand very little about its timing and origins, particularly as a predator avoidance strategy. Understanding the timing between bioluminescence and predator origins has yet to be examined and can help elucidate the evolution of the ecologically important signal aposematism. Using the most prevalent bioluminescent group, fireflies, where bioluminescence primarily functions as aposematic and sexual signals, the timing for the origins of both potential predators of fireflies and bioluminescence is explored. Divergence time estimations were performed using a genomic-scale phylogenetic reconstruction Lampyridae, and multiple fossil calibration points, allowing for a robust estimate for the origin of beetle bioluminescence as both a terrestrial and aerial signal. Our results recover the origins of terrestrial beetle bioluminescence at 141 mya and aerial bioluminescence at 133 mya. These ages predate the origins of all known extant aerial predators (i.e., bats and birds) and support the much older terrestrial predators (frogs, ground beetles, lizards, snakes, and hunting spiders) as the most likely drivers of bioluminescence in beetles.
Competing Interest Statement
The authors have declared no competing interest.