His research efforts have included studies of reproductive isolating mechanisms in sulfur butterflies, reproductive and life history patterns in plants, comparative biology of European and Neotropical African honey bees and migratory behavior of monarch butterflies. Work in progress utilizes genetic markers to quantify the interactions between invading Neotropical African bees and resident European bees in North America. These investigations should clarify why, even after 40 years of hybridization, Neotropical African bees have retained their genetic integrity. Monarch Watch www.MonarchWatch.org , an outreach program he initiated in 1992, now occupies much of his time.

Stable Isotopes of Hydrogen and Carbon are Geographic Indicators of Natal Origins of Monarch Butterflies in Eastern North America. Oecologia (in press).

Mark and Recapture during the Monarch Migration: A Preliminary Analysis. North American Conference on the Monarch Butterfly (in press).

"Timing of Mating Flights of Neotropical African and European Honey Bee Queens and Drones (Hymenoptera: Apidae) in Eastern Venezuela." Journal of the Kansas Entomological Society (in press).

"Genetic replacement of European honey bee (Apis mellifera) subspecies by invading African bees in the Americas." Proc. Int. Workshop on Biol. Invasions of Ecosystem by Pests and Beneficial Organisms, Tsukuba, Japan (in press).

BIO 419: Advanced Biology