Our current work investigates a major ecological transition in echinoderm life cycles: the evolution from planktotrophic to lecithotrophic larval development. We have discovered a wide range of feeding requirements among subtropical echinoid larvae. Differences in maternal investment determine how much external food is required to build the larval body and subsequently the juvenile rudiment. There appears to be a continuum of nutritional strategies between extreme obligate planktotrophy and functional lecithotrophy (i.e. facultative planktotrophy). We suggest that the ecological boundary between planktotrophy and lecithotrophy is easily crossed and that unlike morphological changes, ecological transitions, are readily reversible.