Data from: The biogeography of Sulawesi revisited: is there evidence for a vicariant origin of taxa on Wallace’s “anomalous island”?

Sulawesi, the largest island in the Indonesian biodiversity hotspot region
Wallacea, hosts a diverse endemic fauna whose origin has been debated for
more than 150 years. We use a comparative approach based on dated
phylogenies and geological constraints to test the role of vicariance
versus dispersal in the origin of Sulawesi taxa. Most divergence time
estimates for the split of Sulawesi lineages from their sister groups
postdate relevant tectonic vicariant events, suggesting that the island
was predominantly colonized by dispersal. Vicariance cannot be refuted for
20 % of the analyzed taxa, though. While vicariance across Wallace’s Line
was only supported for one arthropod taxon, divergence time estimates were
consistent with a “tectonic dispersal” vicariance hypothesis from the East
in three (invertebrate and vertebrate) taxa. Speciation on Sulawesi did
not occur before the Miocene, which is consistent with geological evidence
for more extensive land on the island from that time. The Pliocene onset
of periodic sea-level changes may have played a role in increasing the
potential for dispersal to Sulawesi. A more extensive taxon sampling in
Wallacea will be crucial for refining our understanding of the region’s
biogeography and for testing hypotheses on the origin of taxa on its most
important island.