Paleo-island morphometry
To test our hypotheses, we estimated the past insular areas and
distances to the mainland in order to use these metrics as predictors of
current species diversity. Herein, we were interested in the difference
between the present-day geographical setting, the situation during the
LGM and the situation under the median sea level over the last nine
glacial-interglacial cycles (MSL - Norder et al. 2019). Hence, besides
the present-day configuration of the Aegean islands, we used the work by
Simaiakis et al. (2017 – Supplementary Material Appendix 1) for
paleogeographical configurations. To investigate the biogeographical
effects of past fragmentation from the mainland, we classified islands
into two different groups: those that remained isolated from the
mainland, referred to as “true islands” versus those with an
episodic connection to the mainland during the LGM (“LGM land-bridge
islands”) or at median sea level (“median land-bridge islands” -
Simaiakis et al. 2017).