The Mexican axolotl is a salamander used as a non-mammalian vertebrate model system in diverse fields of biological research, including cell biology, developmental genetics, endocrinology, neurobiology, and physiology. The axolotl is also used in classroom exercises by teachers at colleges, high schools and museums. This grant supports the Indiana University Axolotl Colony, which has been the major supplier of mutant strains of axolotl to the scientific community since late 50's. The axolotl center breeds, maintains, and supplies the well-characterized genetic stock of axolotl. It also publishes newsletters to inform the user community of the availability of axolotl and interesting scientific findings obtained through the use of axolotl.