Fig. 4: Estimated phenological advancement.
From: Bird populations most exposed to climate change are less sensitive to climatic variation
Phenological advancement (days advanced/year of great tit (Parus major; triangle) and blue tit (Cyanistes caeruleus; circle) populations in deciduous (orange), mixed (blue), and evergreen (green) dominant habitats. Phenological advancement (background colour) is a product of phenological sensitivity and climate change exposure. A darker background colour represents greater phenological advancement over time. Populations with the highest recorded phenological sensitivity do not show the highest expected phenological advancement due to their lower climate change exposure. Coloured points represent each population’s expected phenological advancement, the product of estimated phenological sensitivity and climate change exposure. Note that phenological sensitivity and climate change exposure are calculated within population-specific temperature windows, which accounts for observed intra-specific variation in temperature window midpoints (Fig. 2). Vertical and horizontal lines represent standard errors of slope estimates for climate change exposure and phenological sensitivity respectively. Number of biologically independent years used to estimate phenological sensitivity for each population is available in Supplementary Data 1. Climate change exposure is estimated in each population using 68 biologically independent years (1950–2017).
