Life at High Latitudes Does Not Require Circadian Behavioral Rhythmicity under Constant Darkness (Current Biology)

Bertolini et al. find that drosophilids inhabiting high latitudes possess a circadian clock that is either not self-sustained or uncoupled from its output. This leads to behavioral arrhythmicity in constant darkness. The authors propose that this feature might be of adaptive value for animals to successfully colonize weakly rhythmic environments.