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Organisms of all shapes and sizes synchronize their behaviors using biological clocks. Some keep pace with the daily rising and setting sun using circadian rhythms. Others use annual cycles or the changing seasons as their cue. But many animals use moonlight and Earth’s lunar cycle to run their biological clock. Do humans do the same thing, with things like menstrual cycles? This week we take a look at living by moonlight.
Menstrual cycle data courtesy of Clue app (
Grunion footage courtesy of KQED’s Deep Look ( and Dr. Michael Murrie – Pepperdine University
The Myth of the Moon and M**********n:
Grant, Rachel, Tim Halliday, and Elizabeth Chadwick. “Amphibians’ response to the lunar synodic cycle—a review of current knowledge, recommendations, and implications for conservation.” Behavioral Ecology 24.1 (2012): 53-62.
Zhang, Lin, et al. “Dissociation of circadian and circatidal timekeeping in the marine crustacean Eurydice pulchra.” Current Biology 23.19 (2013): 1863-1873.
Zantke, Juliane, et al. “Circadian and circalunar clock interactions in a marine annelid.” Cell reports 5.1 (2013): 99-113.
Warren, H. B. Aspects of the behaviour of the impala male, Aepyceros melampus, during the rut. National Museums and Monuments of Rhodesia, 1974.
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