Lunar rhythms in activity, urinary volume and acidity in the golden hamster (Mesocricetus auratus Waterhouse) / Author: Margaret Klinowska.
Published in: Biological Rhythm Research, Volume 1, Issue 4 December 1970 , pages 317 - 322
Quote:Abstract : Mean hourly activity every day and daily urinary volume and pH have been recorded for two groups of male hamsters between autumn 1966 and autumn 1967. The experiments took place under natural lighting conditions indoors with no specific climatic control. Lunar modulations appeared in all records. Urinary volume was greatest on the same day of the lunar month as the minimum for activity, while pH showed maxima around full moon.
Well, I hope that knocks all that uncertainty amongst the A2K community right on the head!