My lab uses different model systems to study the developmental and genetic basis of evolutionarily novel traits. Oligodendrocytes are glial cells that form the myelin sheath in the central nervous system of higher vertebrates. Primitive vertebrates (hagfish and lampreys) lack myelin forming glial cells. In mammals and birds oligodendrocytes develop from stem cells in a specific region of the ventral neural tube. Cells adjacent to this region give rise to astrocytes, a different class of glial cell. We are using conserved genetic markers to determine whether this mechanism of development is also found in fish and amphibians. The second model system we use is the development of the eyestalk in diopsid or stalk-eyed flies. These flies carry their eyes and antennae at the end of these lateral head projections called eyestalks. Male stalk eyed flies have greatly exaggerated eyespans, which are sexually attractive to females. We are using a comparative approach to identify genes involved in regulating eyestalk development. Recently we have developed transgenic technology for stalk-eyed flies, which will allow us to look at the effects of manipulating gene function on eyestalk development directly.