PARENT SESSION
Symposium 20: Evolution on ecological time scales
Organized by: A Hendry, D Réale, and G Fussmann
Thursday, August 11, 1:30 PM - 5:00 PM, Meeting Room 517 B, Level 5, Palais des congrès de Montréal
Rapid evolution of an invasive species.
Alexander, Badyaev*,1, 1 Department of Ecology and Evolutionary Biology, Tucson, Arizona, United States
ABSTRACT- Seventy years ago, a cagefull of house finches (Carpodacus mexicanus) captured in the desert of southern California was released from a pet store in New York City. In the subsequent years, this population together with native populations in the southeastern United States spread across most of North America, ultimately covering the widest ecological gradient of any passerine bird. We report that the rapid adaptive evolution of morphology that accompanied such expansion was enabled by extensive maternal inheritance in this species: the response of traits to selection and the rate of microevolutionary change were determined by the strength of maternal effects on early growth. We report however, that the observed maternal effects on offspring morphology are likely a passive consequence of maternal adaptations to breeding in ecologically distinct conditions. We discuss how environmentally-induced plasticity in maternal breeding behaviors can lead to rapid evolution of local adaptation in offspring morphology in this invasive species.
Key words: maternal effects, microevolution, phenotypic assimilation, hormones