Comparison of linear vs. exponential decay functions
A total of 290 experiments could be fitted with both piecewise
regression and exponential decay models (Fig. S5). The remaining 18
could not be fitted with piecewise regression, which most frequently
occurred because the minimum value of D (i.e. complete
acclimation) was reached at the second observation, in which case
multiple breakpoints can yield an identical fit. Of these 290
experiments, comparisons of their residual standard errors revealed that
the data in 62% (n=180) of cases was best explained by the exponential
decay model. Furthermore, superior fit by piecewise regressions (N = 110
experiments) was observed primarily in experiments where thermal
tolerance was measured at relatively few time points following exposure
of the study organisms to the new temperature (Fig. S6). Thus, for more
comprehensive experiments (i.e. greater number of measurement points in
time), the shape of the plasticity rate response is better described by
an exponential decay function. Thus, in all further analyses we use the
estimates of λE (Table S2).