Calcification in sea urchin larvae is associated with low metabolic costs.

The energetic costs of generating calcium carbonate skeletons and shells in marine organisms remain largely speculative because of the scarcity of empirical data. However, this information is critical for estimating energetic limitations of marine calcifiers that can explain their sensitivity to changes in sea water carbonate chemistry in past, present and future marine systems. Here, the cost of calcification was evaluated using larval stages of the purple sea urchin, Strongylocentrotus purpuratus.