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The Hawaiian silversword alliance is a spectacular example of plant adaptive radiation. The lineage includes 33 species in three endemic genera (Argyroxiphium, Dubautia and Wilkesia) that occupy almost all major habitats of the Hawaiian archipelago. Here, we quantitatively explore functional diversification in the lineage by linking measurements of multiple leaf functional traits with climate niche and phylogenetic data. We show that leaf functional trait variation (i) spans much of the global angiosperm range, (ii) is best explained by a white-noise evolutionary model and (iii) is integrated in ways consistent with both the global leaf economics spectrum and the predictions of leaf venation network theory. Our results highlight the importance of functional diversification and integration in rapidly evolving plant lineages. They also provide compelling additional support for the view that the Hawaiian silversword alliance is one of the world's premier examples of adaptive radiation in plants. The Hawaiian silversword alliance includes 33 species in three endemic genera (Argyroxiphium, Dubautia, and Wilkesia) that occupy almost all major habitats of the Hawaiian archipelago (top row). We show that leaf functional trait variation in the lineage spans much of the global angiosperm range, is best explained by a white-noise evolutionary model, and is integrated in ways consistent with both the global leaf economics spectrum and the predictions of leaf venation network theory (bottom row). The results provide compelling support for the view that the silversword alliance is one of the world's premier examples of adaptive radiation in plants. Journal of Ecology

Native plant species that have lost their mutualist partners may require non-native pollinators or seed dispersers to maintain reproduction. When natives are highly specialized, however, it appears doubtful that introduced generalists will partner effectively with them. We used visitation observations and pollination treatments (experimental manipulations of pollen transfer) to examine relationships between the introduced, generalist Japanese White-eye (Zosterops japonicus) and 3 endemic Hawaiian plant species (Clermontia parviflora, C. montis-loa, and C. hawaiiensis). These plants are characterized by curved, tubular flowers, apparently adapted for pollination by curve-billed Hawaiian honeycreepers. Z. japonicus were responsible for over 80% of visits to flowers of the small-flowered C. parviflora and the midsize-flowered C. montis-loa. Z. japonicus-visited flowers set significantly more seed than did bagged flowers. Z. japonicus also demonstrated the potential to act as an occasional Clermontia seed disperser, although ground-based frugivory by non-native mammals likely dominates seed dispersal. The large-flowered C. hawaiiensis received no visitation by any birds during observations. Unmanipulated and bagged C. hawaiiensis flowers set similar numbers of seeds. Direct examination of Z. japonicus and Clermontia morphologies suggests a mismatch between Z. japonicus bill morphology and C. hawaiiensis flower morphology. In combination, our results suggest that Z. japonicus has established an effective pollination relationship with C. parviflora and C. montis-loa and that the large flowers of C. hawaiiensis preclude effective visitation by Z. japonicus.