Supplementary Fig. 4. SDD calculated at the cluster/species level for the NWE province and the MED province for each chronozone of the early Pliensbachian, after grouping the species according to the volume of their shell

Similarity distance decay calculated at the cluster/species level for the NWE province (A-F) and the MED province (G-L) for each chronozone of the early Pliensbachian, after grouping the species according to the volume of their shell (V = ln(volume) in mm3), in order to determine if there is a relationship between shell size and long-distance dispersal. For each province, the lower graphs represent the small species and the upper graphs the large ones. Only clusters with at least 3 species are considered in these analyses. The black lines are the Ordinary Least-Square linear regressions and the SDD rates are the values of their slopes.