Endemism and evolution in Hawaiian marine invertebrates.

Endemism in Hawaiian marine invertebrates is strikingly lower than that in Hawaiian terrestrial organisms. Although marine speciation has been widespread, there have been no major radiations or species swarms comparable with those commonly reported for terrestrial animals and plants; the marine fauna of the Hawaiian islands is differentiated from its Indo-west Pacific roots but has not diversified. The marked differences between marine and terrestrial endemism provide broad support for several models in which speciation depends on dispersal, colonization rate, or effective population size. Distinguishing among these models will require detailed information on the genetic structure and phylogenies of marine species both in the Hawaiian archipelago and throughout the Pacific.