Foraminiferal biomineralization: mechanisms, calcite chemistry and evolution

Many foraminifera form shells made of calcium carbonate. The elemental and isotopic composition of these shells varies greatly from inorganically precipitated calcites, suggesting a strong biological control on the process of CaCO₃ precipitation. Moreover, this composition differs, sometimes greatly, between species, which may indicate that the controls on calcite chemistry is not fixed among all species. For paleoceanographic application, a better grip on this inter-species variability in calcite chemistry is necessary. Here we present the latest insights in environmental controls on element incorporation, biomineralization mechanisms and evolutionary patterns in biomineralization. An integrated understanding of foraminiferal calcification will also allow predicting their response to changes in marine inorganic carbon chemistry (e.g. ocean acidification), which in turn, is necessary to assess the contribution of changes in foraminiferal calcification rates to (surface) marine inorganic carbon cycling.