Figure 2.

Altitude component for a) aphids b) birds c) butterflies and d) moths from the baseline trend model (Equation 1). The estimated smoothed terms are a transformed function of altitude which on the y‐axis is centred on zero and scaled by the effective degrees of freedom. The graphics show the estimated smoother effects with 95% confidence intervals in grey, where positive trends yield later phenologies with increasing altitude. The x‐axis has two components; the major tick marks indicate numerical values and above those are rug plots that show the distribution of altitudes in the original dataset, which are irregularly spaced. Note how the confidence interval widens as fewer phenological observations are recorded at higher altitudes