Thermal plasticity in development and diapause strategy in a temperate butterfly across a latitudinal gradient

Trade-offs among traits are central to life-history theory and often closely linked to an organism’s fitness. Understanding how these trade-offs vary among populations and across environments is therefore important to more accurately predict species’ responses to future climate change. However, the extent to which responses vary across populations remains unknown because few studies investigate intraspecific differences. 
We performed a full-factorial split-brood common garden experiment to test how variation in rearing temperature affects developmental timing and other traits important for survival during diapause in the Glanville fritillary butterfly (Melitaea cinxia). Pre-diapause larvae originating from four regions across a latitudinal cline across Europe were reared at four temperatures (25, 28, 31, and 34 °C), and we used a reaction norm approach to test for evidence of genetic differentiation and variation in developmental plasticity across regions.
We found clear signs of gene...