Evidence for both long‐distance dispersal and isolation in the Southern Oceans: molecular phylogeny of Sophora sect Edwardsia (Fabaceae)

A molecular phylogeny of Sophora sect. Edwardsia (Fabaceae) reveals both long-distance dispersal and isolation patterns in the Southern Oceans. The study found that while chloroplast and nuclear sequences are shared across vast geographic distances, species on Pacific Islands like Lord Howe Island, Easter Island, Hawaii, and French Polynesia exhibit unique haplotypes, indicating genetic isolation. Notably, the S. chrysophylla haplotype is more closely related to those from French Polynesia than to S. denudata from Réunion Island, despite shared morphological traits. The research used DNA sequences from chloroplast spacers (trnQ-5′rps16 and trnH GUG-psbA) and the nuclear-encoded glutamine synthetase gene, analyzed through median-joining networks and phylogenetic approaches. This suggests complex evolutionary histories shaped by both dispersal and isolation in the region.

Shepherd, L. D., & Heenan, P. B. (2017). Evidence for both long‐distance dispersal and isolation in the Southern Oceans: molecular phylogeny of Sophora sect Edwardsia (Fabaceae). New Zealand Journal of Botany, 55(3), 334–346. Portico. https://doi.org/10.1080/0028825x.2017.1353527