This research project is a genetic survey of reef fishes across the broadest continuous habitat in the world: the tropical Indo-Pacific from Africa to the Americas. The survey will include 15 species and assess population connectivity among island archipelagos, in direct support of a research mandate by the NSF Biological Oceanography Program. This project is designed to address three contemporary issues in marine biology: 1) How did reef fish colonize Hawaii? This archipelago is among the most isolated reef habitats in the world. The primary currents systems of the Pacific flow above or below Hawaii, so it is uncertain how reef fauna dispersed to this area. The two prevailing theories are that they colonized from the West Pacific, or from the South Pacific. Changes in ocean circulation during glacial periods may have enhanced colonization opportunities. In this project, gene genealogies from mtDNA and nuclear DNA will reveal the pathways of colonization, and the age of these events. 2) What are the genetic separations among Indian and Pacific Oceans? During low sea levels associated with glaciation, the Pacific and Indian Oceans are separated by a land bridge between Asia and Australia. The reef fish phylogeography project will test the age and permeability of this barrier. 3) Is the Indo-Pacific core a center of speciation? Is the high diversity in the central Indo-Pacific due to speciation within this region, or accumulation of species that evolve on peripheral islands? The study will address these alternatives with gene genealogies, to resolve fundamental evolutionary processes.
Broader Impacts: The dire conservation status of coral reefs is well documented, and one of the most effective responses is marine protected areas (MPAs). In order to design MPAs, Pacific island nations need to know the level and direction of dispersal among reef ecosystems. The research will define historic patterns of reef fish (larval) dispersal across the Pacific and Indian Oceans, with special emphasis on Hawaii and the U.S. territories. It will recruit Indo-Pacific island students to collect fin clips for phylogeographic analysis, usually supervised by a local biology professor. The students participate in this research, view the results, and discuss how findings can influence management of local reef resources. These teams also receive a modest bounty which can be used to upgrade science education materials. This program is also an opportunity to recruit exceptional Pacific Island students to the University of Hawaii. This project will complement a parallel survey of reef invertebrates and a survey of deep reef fishes. By combining effort in collections and data analysis, investigators can greatly enhance both the efficiency and the value of these projects. Hawaii Institute of Marine Biology has developed a molecular genetic core facility dedicated to coral reefs and associated fauna. With current NSF funding, the PI has developed a center for training in rebreather diving technology to open new frontiers in ocean exploration. The project will enhance the momentum of this unique facility, and provide research opportunities to the diverse community at University of Hawaii.
