Résumé
Traditionally, diatoms have been associated with productive pelagic food chains that lead, through suspensionfeeding planktonic copepods, to top consumers and important fisheries. Here, 15 laboratories located worldwide in 12 different countries and representing a variety of marine, estuarine and freshwater environments present strong evidence that diatom diets are in fact inferior for copepod reproduction. When fed to females of 16 copepod species, all but 1 of the 17 diatoms examined significantly reduced egg production rates or egg viability compared to non-diatom controls. These effects are hypothesized to influence copepod recruitment patterns and the flow of energy in marine food webs.