Professor of Biology and Department Chair
I love biological diversity - particularly arachnids. From the moment I learned about how little we know about the living organisms that share our world, and I realized I could contribute to understanding it, I’ve been hooked! Issues of biodiversity are infused into all courses I teach, the public outreach I do, and are the central focus of my research program at Lewis & Clark College.
Spiders are a great vehicle for studying biodiversity. They are among the most conspicuous and abundant terrestrial arthropods yet much about them remains to be discovered. They spend time eating insects, decorate our world with gorgeous webs, and males dance to court females (seriously!). As if that’s not enough, they make silk fibers with remarkable material properties, and venoms rich in peptides and proteins that are not found anywhere else. Very few spiders have venoms that can hurt people, and even fewer are aggressive to humans. The work my students and I do helps us better understand these animals and their venoms. We also help people understand the many unseen ways these animals contribute to our world.
Prospectives in Biology - Arachnology/Biodiversity (BIO 100)
Investigations in Genetics and Evolution (BIO 151)
Invertebrate Zoology (BIO 212)
Evolution (BIO 390)
Phylogenetic Biology (BIO 408)
The chemical richness and diversity of spider venoms make them interesting subjects for understanding how evolution generates novelty. My research program uses integrative, evolutionary approaches to better understand patterns of diversity in spider venoms. In my lab, students participate in evolutionary analyses of spider venoms at all levels of the process. This includes collecting a range of spiders in the field, doing protein analyses of the venoms, and using molecular approaches to study the genes that code for the venom proteins. We also are studying the evolutionary history of the spiders themselves to create a framework we can use to analyze venom evolution. Students also analyze the effects of venoms on insect prey and observe spider foraging behavior. These data help to better understand the role venom plays in immobilizing prey and how that varies across spider species.
Our current research is focused on brown recluse and their relatives (Loxosceles). We have discovered that the toxin in venoms of Loxosceles that causes dermonecrotic lesions (sphingomyelinase D) is also present in venoms of some species in the closely related genus Sicarius. This means this toxin likely originated in an ancestor of these two types of spiders. This knowledge helps us better understand the range of species related to the brown recluse that is capable of causing lesions when these animals bite people. Knowing how the toxin varies among species may help to facilitate development of treatments that will work for bites of all members of this group of spiders.