The proposed work will focus on understanding calcification by marine organisms and will challenge the long-standing view that precipitation occurs via classical crystallization processes. The interpretation of many past studies is based on this notion. It now appears that most carbonate-producing organisms form skeletons by non-classical growth processes which involve an amorphous phase that transforms to a composite of mesocrystals over time. If this is true then the current approaches to inferring environmental effects, and interpreting paleo records, from analysis of calcite skeletons, either recently formed or preserved in marine sediments, will need to be revised as skeleton formation by non-classical processes relies on a different set of chemical and environmental conditions. The proposed research will build on recent findings which suggest that acidification, magnesium concentration, biomolecule chemistry and other factors all influence this pathway to mineralization. The project will investigate a number of hypotheses based on this new paradigm using laboratory studies and innovative analytical approaches. Kinetic and thermodynamic measurements and modeling will be coupled with chemical and structural investigations to establish a complete physical picture of the biomineralization pathway.
The scientific broader impacts of the research go beyond the field of Chemical Oceanography and will have substantial impact if the proposed hypotheses are confirmed. The project has significant educational aspects, with the inclusion of both graduates and undergraduates in the research, and K-12 education development through the NSF-funded Earth to Life series.
