Meeting Abstract

P2.30  Sunday, Jan. 5 15:30  Adaptation to thermal stress in a Finnish butterfly threatened by climate change DAHLHOFF, VC*; IKONEN, S; HANSKI, I; DAHLHOFF, EP; Bates College; University of Helsinki; University of Helsinki; Santa Clara University edahlhoff@scu.edu

A consequence of climate change is that organisms living at high latitude may experience increased exposure to thermal extremes due to warmer summers and drier winters. These more severe conditions may adversely affect population persistence due to alteration of individual performance or reproduction. In a metapopulation of the butterfly Melitaea cinxia found on the Aland Islands of Finland, extirpation and re-colonization is linked to differences in dispersal, which is dependent on differences in flight metabolic rate among phosphoglocuse isomerase (Pgi) genotypes. Here we report that thermal tolerance (CTmax, LT50), flight performance, and metabolic rate are highest for Pgi heterozygotes after mild heat stress, but after extreme stress, individuals homozygous for a Pgi allele common in Central Europe, but rare in Finland, performed or survived best. Furthermore, male mating activity was reduced after exposure to elevated temperatures regularly experienced in nature. Ongoing studies will determine if genetic differences later effects of temperature on male mating success. Taken together, these data suggest that Finnish populations of M. cinxia may be vulnerable to stressful environmental conditions that may become more common as climate change proceeds.