Differences in thermal niche between coastal and inland populations of the yellow monkeyflower (Mimulus guttatus)

Climate change will have multiple important impacts on coastal plant communities, yet how coastal plants will respond to temperature increases is understudied. Coastal areas experience small fluctuations in temperature daily and annually, similar to lowland tropical environments where research has shown that some tropical organisms are extremely threatened by increases in temperature because their thermal environmental has, historically, been very stable. Using multiple approaches, we plan to study if coastal and inland populations of the plant Mimulus guttatus differ in the evolution of their thermal niches. Are coastal populations more sensitive to changes in temperature, have coastal populations been limited in their thermal niche evolution, and are coastal populations more vulnerable to climate change? To test these questions, we have compared the evolution of habitat and temperature seasonality on a phylogeny of populations across the range of M. guttatus. We plan to compare relative growth rate between coastal and inland populations under different temperature treatments in growth chambers to understand how thermal niche currently differs and predict how populations may fair under climate change.