Animals such as sea stars, sea urchins and sea lilies bury much more carbon than anticipated, according to the first study to estimate echinoderms’ contribution to ocean carbon storage.
Studies of biological carbon in the oceans tend to focus on organisms that drift through the shallows, such as plankton, because they are known to store carbon in the form of calcium carbonate, which they transport to the sea floor when they die.
Mario Lebrato suspected that bottom-dwelling animals such as echinoderms also store large amounts of calcium carbonate, and wondered how large a role they might have in the global carbon cycle.
While still an undergraduate at the University of Southampton, UK, Lebrato, now a PhD student at the Leibniz Institute of Marine Science in Germany, set out to study the rates at which echinoderms absorb calcium carbonate and what happens to the carbon when they die. “The funding for this was initially derived from my pocket because nobody believed in the echinoderm [carbon] contribution,” says Lebrato.