Most zooplankton, and some benthic animals, reproduce continuously. As a population changes by addition and growth over a given time interval, a demographic turnover occurs [see reviews of Edmondson (1974) and Rigler and Downing (1984)]. Few, if any, of the individuals present at the peak of an exponentially developing population were alive at the beginning of the exponential phase. An individual also undergoes a biochemical turnover during its lifetime so that, upon completing a mean lifespan, it will have assimilated several times its final mass.
KeywordsSize Category Stratify Lake Daphnia Population Zooplankton Production Continuous Reproduction
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