Geographic variation among monarch butterfly populations
We have examined geographic variation in phenotypic traits of monarch butterflies from different populations in North America and Hawaii. Monarch butterflies populate islands and continents worldwide, including North America, South and Central America, Caribbean and Pacific Islands, and Australia. In temperate regions monarchs undergo long-distance migration, but in tropical locations the butterflies can breed-year round and do not migrate. Monarchs in these populations experience different degrees of geographic isolation and are exposed to different climates, host plant species, and natural enemies. Divergent selective forces may have influenced traits associated with monarch flight ability, including wing size and shape, and monarch responses to different host plant species and performance in different thermal regimes.

 Recent and ongoing projects include:

Digitally measuring and comparing adult wing size, shape and color across all populations

Digitally measuring and comparing temperature-induced larval coloration across all populations

Comparing female oviposition preferences and larval performance of eastern and western North American monarch butterfly populations

Comparing the effects of extreme temperatures on larval survival and growth rates across monarch populations in North America