U.S.-JAPAN COOPERATIVE SCIENCE: BIOGEOGRAPHIC HISTORY OF NORTHERN HEMISPHERE COASTAL FISHES (PHOLIS AND CHIROLOPHIS):

Duke University, Durham NC

Investigators

Abstract

0203094 Cunningham This award supports a one-year collaborative research project between Professor Clifford Cunningham at Duke University in North Carolina and Professor Hisashi Imamura at the Hokkaido University Museum in Japan. The researchers will undertake a study of the biogeographic history of northern hemisphere coastal fishes (pholis and chirolophis). They will use multi-locus DNA sequence data (mtDNA d-loop, nuclear a-enolase, and nuclear a-tropomyosin) in conjunction with morphological data to investigate how past climate changes and ecological shifts (changes in vertical depth) have affected patterns of speciation and morphological evolution in temperate rocky coastal fishes of the superfamily Stichaeidae (Yatsu 1985). Their research will be undertaken in Japan, Wales, Norway and Iceland. The findings of this study will illuminate our understanding of the timing, conditions and consequences of speciation in temperate coastal fishes. Although we know little about the causes of speciation in temperate coastal fishes that are restricted to a single ocean, DNA sequence data has the ability to distinguish between different allopatric speciation explanations as well as explanations that invoke changes in vertical depth. The project brings together the efforts of two laboratories that have complementary expertise and research capabilities. The U.S. researchers have expertise in many of the fish species being studied and the Japanese researcher is Japan's foremost intertidal fish specialist. Results of the research could suggest that the present species diversity found in temperate marine coastal fish assemblages is largely the result of the Earth's periodic and extreme climate changes of the last 10 Mya. This would mean that changes in oceanographic conditions brought on by climate changes could have separated conspecific populations of marine taxa, even in the face of gene flow via planktonic larvae. The research could also suggest that speciation in coastal fishes was associated with invasions of new habitat depths, such as a subtidal species invading the intertidal with subsequent reproductive isolation between the two intraspecific ecotypes. The research will offer a good opportunity to join efforts between the two countries. Through the exchange of ideas and technology, this project will broaden our base of basic knowledge and promote international understanding and cooperation. A graduate student will also be participating in the research. The researchers plan to distribute the results of their findings through the Web, publications and presentations at conferences.