Figure 1.

Increase of the probability of extremes and consequences for evolution of a quantitative trait and population size over time. Increase in variability for 25 years after climate change β_σ,Θ = 0.5 (a–c), 1.0 (d–f), 1.5 (g–i), 2.0 (j–l) × 10⁻². For all rows, β_μ,Θ = 2 × 10⁻². (a,d,g,j) Shift of the normal distribution of a climate variable (e.g. mean or maximum summer temperature) from year 1 (start of simulation time, grey line) to year 300 (end of simulation time, black line), with a directional increase of the mean of the distribution β_μ,Θ and increase in the variability of the optimum from year 150 to year 175 (β_σ,Θ). The grey region defines the events in the distribution of the climate variable at the end of simulation time that would be considered extreme events at t = 1 (e.g. in the right 2.5% of the distribution). (b,h,h,k) Example of change of the optimum phenotype Θ(t) through simulation time (grey) and change of the mean phenotype (black). The dashed lines define the 95% central portion of the normal distribution of the climate variable at t = 1. (c,f,i,l) Population size though time with variation of the optimum phenotype as in (b,h,h,k). Vertical segments indicate point extreme events with p(E_a) = 7.5 × 10⁻².