Lechosław Kuczyński

1 INTRODUCTION Ongoing anthropogenic global change is causing unprecedented changes in the functioning of entire populations, communities and ecosystems (Pecl et al., 2017). As a result, the abundance and distribution of many species are changing dramatically, creating dynamic spatiotemporal patterns. Several classes of process-explicit models have been proposed to study species range dynamics (Briscoe et al., 2019). However, assessing the validity of these models is not a straightforward task.

INTRODUCTION The astounding diversity of life on Earth has always intrigued and inspired biologists, and for many decades has motivated research into the mechanisms of its maintenance (Chesson, 2000a, 2000b; Hubbell, 2001; Hutchinson, 1961; MacArthur, 1972). However, the drivers of diversity are complex and challenging to understand, as species interact both with the environment and with other species (Chesson, 2000b; HilleRisLambers et al., 2012).

Step 6: Model evaluation Reconstructed response curves were compared with those used to generate the VS by calculating the coverage probability (% of the time when the 95% CI of the fitted response curve contains the true value). The same procedure was applied to evaluate estimated population trends. The ‘true’ population trend was calculated as the slope of yearly log-transformed population density means taken from the VS.