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Updated: Jul 12, 2026

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents
Published on: January 24, 2013
Vertical diurnal migration and endogenous rhythmicity
Abstract:
Experimental studies of mixed populations of marine zooplankton have demonstrated that internal rhythms, synchronized by a light-dark cycle, are of dominant importance for the vertical migration of several species of crustaceans. For certain other organisms, the vertical migrations observed in the experiments can be accounted for as direct responses to light intensity only. Performances intermediate between these extremes were also observed, as well as behavior based on biological timing mechanisms that are not rhythms in the usual sense.
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