Researchers

Using the general approach of stable isotope geochemistry, I have worked on various projects in the Sonoran Desert over the last twenty years. My work on the Colorado River delta looked at seasonal isotope ratios in mollusk shells as a record of river flow through time. Mollusk shells and fish otoliths are also the topic of work on the seasonality of native American usage of marine resources in the Northern Gulf of California. In addition I have been involved in work on the ecology, growth, and fitness of saguaro cactus across an aridity spectrum based on stable isotope ratios in spines. This work has recently been expanded to include multiple species of columnar cactus across the Americas. I was one of the early members of this network, but had fallen off the membership list.