Marine Calcification: An Alkali Earth Metal Isotope Perspective

Calcium and magnesium isotope fractionation, recorded in shells of marine organisms that biomineralize calcium carbonate, is helping scientists to understand the transport of trace elements from seawater to the site of calcification, as well as trends in seawater composition throughout time. This knowledge would be difficult to obtain otherwise, and is important, especially now, for assessing the threat of ocean acidification to shell-producing marine organisms.