Vertebrates have numerous developmental genes, and a given function is often performed by several related genes. Consequently, if a single gene is experimentally deactivated or naturally defective, several other genes can cover for its function. This makes it hard to work out the relationships between different genes and their functions. Amphioxus is closely related to vertebrates, yet has far fewer developmental genes (~ 20% of vertebrate genes). Amphioxus is therefore a promising organism in which to study the genes that direct the formation of the vertebrate-like body plan. Although an increasing number of developmental biologists would like to study amphioxus, the animals are only available in a few marine habitats and ripe for two months out of the year. Dr. Holland would like to extend the utility of amphioxus through the entire year by developing aquaria with controlled light cycles, temperature and food regimes, thus permitting amphioxus to be studied at laboratories far from sea coasts. The culture system is designed to be user-friendly and to ensure a reliable supply of healthy eggs and sperm for molecular genetic studies of amphioxus. These automated aquaria will also permit mutant amphioxus strains to be maintained from one generation to the next in the laboratory. Dr. Holland will provide instructions for building and maintaining the aquaria and for raising amphioxus to the developmental biology community via web pages comparable to those now available to biologists working on zebrafish.