Abstract
The spontaneous locomotor activity of 86 penultimate‐hour crabs was studied during the last 4 summers in constant darkness, and in normal and reversed light/dark cycles. In constant conditions some of the individuals exhibited only solar‐day rhythms, some displayed only tidal rhythms, and some described both. The normal and reversed light/dark cycles entrained the solar‐day rhythm, but produced only masking and relative coordination in the tidal components. In 3 crabs, one of the two tidal peaks split, indicating that these peaks can act independently of one another. This suggests that the tide‐associated display of Sesarma—like 5 other crab species—may use two circalunidian clocks, one to control each peak in this rhythmic display.
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.
