Echinoid taxa span three benthic trophic levels, suggesting expansion of niches.
Evidence of nutrient partitioning among coexisting taxa was found in carbon data.
Echinoids incorporate foods with higher δ15N values than that of POM and sediment.
Surface phytodetritus was incorporated into the gonads of the seasonal breeder.
It was incorporated in somatic tissues of continuous breeders, or not at all.