Rethinking the marine carbon cycle: Factoring in the multifarious lifestyles of microbes

Changing tastes in marine microbe food webs Protists are single-celled organisms complete with nuclei, organelles, and symbionts, and possess a multiplicity of physiological talents. They are ubiquitous, abundant, and often neglected by science. Worden et al. review the challenges of understanding the role protists play in geochemical cycling in the oceans. These organisms can photosynthesize like plants, graze on bacteria and archaea, parasitize each other and bigger creatures, have sex, and sometimes do all these things serially as conditions change. Their activities may have a significant influence on carbon cycling, and research efforts need to be amplified to understand their functional importance in marine ecosystems. Science , this issue 10.1126/science.1257594