Abstract
The photoperiodic responses of Drosophila auraria are shown to involve its circadian system functioning as the "clock" that measures the duration of darkness at night. Attempts at further clarification of this finding were based on the widely held assumption that adaptive adjustment of critical night length is caused by change in the circadian system's entrainment behavior. Three different experimental programs yielded data that are incompatible with this starting premise. Collectively, the observations suggest a new interpretation of the lability (phenotypic and genetic) of critical night length based on change in the level of response to all night-length measurements-not on the measurements themselves. This proposition is found especially relevant to the temperature dependence of photoperiodic responses and its role in controlling the onset and termination of the breeding season at different latitudes.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
