The role of a non-native host plant in altering the seasonal dynamics of monarch development

Abstract

The development and life history of many organisms have evolved to align with annual seasonal changes, but anthropogenic ecological changes have started to disrupt phenological dynamics. To understand the implications of these changes, tractable model systems are needed to identify the causes and consequences of phenological-seasonal asynchrony. Here, we investigate the potential of a non-native and tropical host plant whose phenology has been tuned to different seasonal dynamics to influence the seasonal developmental dynamics of the migratory monarch butterfly Danaus plexippus. Consistent with predictions, we found that the non-native host plant facilitated successful monarch development later into the fall and early winter, which is typically the season North American monarchs enter reproductive diapause and migrate to over-wintering locations. Furthermore, we found evidence that this success could partly be attributed to decreased thermal constraints on development experienced by monarchs reared on A. curassavica.