New research suggests that bioluminescence, the ability of living organisms to produce light via chemical reactions, first emerged in animals approximately 540 million years ago. This discovery, based on the study of octocorals, an ancient group of marine invertebrates that encompasses soft corals, significantly predates the previously known oldest example of the trait by nearly 300 million years. Bioluminescence has independently evolved at least 94 times in nature and plays a crucial role in various behaviors, including camouflage, courtship, communication, and hunting.
Researchers, led by Andrea Quattrini, curator of corals at the Smithsonian’s National Museum of Natural History in the US, and Danielle DeLeo, a museum research associate and former postdoctoral fellow, utilized an extensively detailed evolutionary tree of octocorals constructed in 2022. This tree, based on data from 185 species, allowed researchers to determine the approximate time of lineage divergence and the presence of luminous species within the branches. Through statistical techniques and ancestral state reconstruction analysis, the team concluded that the common ancestor of all octocorals likely possessed bioluminescence 540 million years ago.
This finding challenges the previous record held by glowing ostracod crustaceans, which were believed to have evolved bioluminescence around 267 million years ago. The high prevalence of bioluminescence among the thousands of extant octocoral species suggests that the trait has contributed to the group’s evolutionary success. The findings are detailed in the Proceedings of the Royal Society B Biological Sciences journal.
