Active versus inactive bacteria: size-dependence in a coastal marine plankton community

The probability of a bacterium being active was a linear function of its size. Results: support the hypothesis that very small bacteria are mainly dormant (inactive) while bigger bacteria are more likely to be active; reconcile the observations of commonly found higher specific activities in the larger size classes of bacterioplankton and the allometry regularities by which smaller unicellular organisms tend to have higher specific growth rates than larger organisms of similar metabolic mode; and suggest that phagotrophic protists will preferentially crop the active portion of the bacterial community if they select their prey according to size. -from Authors