Reconstructing the complex evolutionary history of the Papuasian Schefflera radiation through herbariomics

The Papuasia floristic region, comprising New Guinea and its surrounding islands, represents an ideal natural experiment in biogeography due to its high plant endemism, complex geological past, and location between the Southeast Asian archipelago and the Australian continent. However, the evolutionary history of Papuasian plants remains poorly understood because herbarium specimens from the region are scarce and scattered (limiting the usefulness of morphological analyses) and often several decades old (resulting in fragmented DNA that is unsuitable for traditional Sanger sequencing approaches). Our study capitalises on these historical herbarium specimens and novel high-throughput sequencing technology (Hyb-Seq, a combined target capture and genome skimming approach) to produce the first ever time-calibrated phylogeny for a mostly Papuasian plant lineage.