My research is motivated by a desire to understand the evolutionary processes that have formed the world in which we live and that have given shape to its history.  The particular segment of Earth history in which I work is the Ordovician Period.  My work employs the principles of comparative morphological analysis, phylogenetic systematics, taphonomy, and biostratigraphy.  My approach in all of these is to test specific hypotheses by quantitative means when ever possible but also to keep sight of the unique properties of biological and geological phenomena.  This uniqueness is the source of the fascination that I feel for the past.

 Graptolites are the fossils on which I specialize.  Their evolutionary history and excellent fossil record provides one of the most important sources of temporal order and stratigraphic correlation for rocks formed during the Ordovician and Silurian periods.  Because of this practical significance, graptolites have been widely studied.  The combination of these features makes graptolites an ideal subject to study both Earth history and the processes of biological evolution.

 Field work is also a central part of my research.  Because graptolites are widespread, this work takes me to field sites in western Newfoundland, China, Argentina, and Bolivia, to name a few recent destinations. Next summer (2006) several of my research colleagues, a student working with me, and I are off to recollect a key section in remote far eastern Siberia!

Recent Destinations

My research is concentrated in three areas:

 Graptolite evolutionary history

 Ordovician chronostratigraphy

Appalachian Basin history