Bivalves in more nutrient-rich environments like the East Pacific invest less in each egg, producing smaller eggs and larvae shells (P1), while those in less nutrient-rich areas like the Caribbean invest more in larger eggs and P1s. To test this, the author compiled egg and P1 size data for bivalve genera in both regions. Preliminary results found Caribbean eggs and P1s were larger on average, supporting the hypothesis. More data is needed to strengthen the results, but nutrient availability seems to impact bivalve reproductive strategies.