Dr. Jansen's research encompasses a wide range of topics in systematics, evolution, and conservation biology. In each of these areas the primary focus of the work has been to understand plant biodiversity by constructing a phylogenetic framework using various kinds of DNA characters. The basic premise of this work is that one cannot address biological questions without first having a comprehensive understanding of evolutionary relationships. Phylogenies are critical for identifying separately evolving lineages that should be targeted fro conservation efforts. He has published over 90 papers on these topics, and his research has been funded by the National Science Foudation and the National Geographic Society. During the past three years the primary focus of Dr. Jansen's lab has been directed toward examining the origin, evolution, and conservation biology of endemic plants from the five archipelagos that comprise Macaronesia.