Rendezvous at night – how moonlight fine-tunes animal reproduction

Animals possess circadian clocks, or 24 h oscillators, to regulate daily behavior. These typically take their cues from the periodic change of sunlight and darkness. However, many animals are also exposed to moonlight, which re-occurs with ~25h periodicity The labs of Florian Raible at the Max Perutz Labs, a joint venture of the University of Vienna and the Medical University of Vienna, and Kristin Tessmar-Raible (Max Perutz Labs, Alfred Wegener Institute, University of Oldenburg) have now discovered that moonlight adjusts the daily clock of marine bristle worms, which helps them to fine-tune their reproductive cycle to certain hours during the night. The study, published in the Proceedings of the National Academy of Sciences, provides an explanation for the phenomenon that daily clocks from flies to humans can exhibit plastic run-times.