Ancestral range reconstruction of remote oceanic island species of Plantago (Plantaginaceae) reveals differing scales and modes of dispersal

A groundbreaking study challenges long-held assumptions about the biogeographical origins of Plantago species, revealing that highly remote oceanic islands like Hawaii and Rapa Iti were colonized from North American taxa via dispersal patterns linked to large marine birds, rather than from New Zealand as previously hypothesized. The research, utilizing Bayesian phylogenetic and divergence time analyses along with historical biogeographical modeling, demonstrates that island endemics in the Lord Howe Island Group, among others, trace their origins to the nearest continental areas. This study highlights the complex interplay of stepping stone dispersal and extreme long-distance dispersal in shaping insular floras, while also suggesting specific traits may limit diversification in island archipelagos. The findings significantly enhance our understanding of floristic exchange between continents and islands, providing critical insights into the ancestral ranges and dispersal routes of widespread plant lineages.

Iwanycki Ahlstrand, N., Verstraete, B., Hassemer, G., Dunbar‐Co, S., Hoggard, R., Meudt, H. M., & Rønsted, N. (2019). Ancestral range reconstruction of remote oceanic island species of Plantago (Plantaginaceae) reveals differing scales and modes of dispersal. Journal of Biogeography, 46(4), 706–722. Portico. https://doi.org/10.1111/jbi.13525