Colorado Resurvey of Pierids

We have been investigating the interplay between phenology, phenotypic plasticity, and evolutionary adaptation in response to climate change. Our research focuses on a key thermoregulatory trait (wing color, which affects absorptivity of solar radiation) of Colias butterflies in montane, seasonal environments. An a priori expectation was that climate warming will select for lighter wings at low elevation (thus reduced heat loads) but darker wings at high elevation (to capitalize on warming). We extended our mechanistic modelling framework that incorporates microclimate, heat balance, and demographic models to include evolution and plasticity. We found – as we predicted – that evolutionary selection favors wing lightening at low elevation but wing darkening at high elevation across the butterflies’ distribution. Importantly, however, we found that seasonal and annual variation in climate causes the strength and direction of selection to fluctuate.

Our models suggest that plasticity in wing absorptivity can facilitate evolution, particularly at lower elevations with long seasons, by reducing temporal variation in the strength and direction of evolutionary selection. Phenological shifts caused by environmental effects on developmental rate can also reduce variation in selection. By using lab and field experiments and museum specimens to test our models, we confirmed model predictions in part but also highlighted how the interactions of multiple responses (e.g., plasticity and evolution) complicate phenotypic shifts. Extending the models to biogeographic scales and to future environments suggests that evolution and plasticity will shape responses, and that evolutionary lags may ultimately confer sensitivity, to climate change.

Collaborators

Joel Kingsolver, Heidi MacLean, Jessica Higgins, Matt Nielsen, Lauren Buckley

Products

Buckley LB and Kingsolver JG. 2019. Environmental variability shapes evolution, plasticity, and biogeographic responses to climate change. Global Ecology and Biogeography 28:1456-1468.

MacLean HJ, Nielsen ME, Kingsolver JG, and Buckley LB. 2019. Using museum specimens to track morphological shifts through climate change. Philosophical Transactions of the Royal Society B 374:20170404.

Kingsolver JG and Buckley LB. 2018. How do phenology, plasticity and evolution determine the fitness consequences of climate change for montane butterflies? Evolutionary Applications 11:1231-1244.

Kingsolver JG and Buckley LB. 2017. Evolution of plasticity and adaptive responses to climate change along climate gradients. Proceedings of the Royal Society B 284: 20170386.

MacLean HJ, Kingsolver JG, and Buckley LB. 2016. Historical changes in thermoregulatory traits of alpine butterflies reveal complex ecological and evolutionary responses to recent climate change. Climate Change Responses 3:13.

Kingsolver JG and Buckley LB. 2015 Climate variability slows evolutionary responses of Colias butterflies to recent climate change. Proceedings of the Royal Society B 282: 20142470.