CAREER: Molecular Systematics of Ray-finned Fishes

University Of Nebraska-Lincoln, Lincoln NE

Investigators

Abstract

9985045 Orti The ray-finned fishes (Class Actinopterygii) comprise the largest group of living fishes, with more than 23,000 species. They are the most successful of all vertebrate classes and a key component to understanding the evolutionary radiation of vertebrates. Although a well-corroborated hypothesis of relationships among all major groups of ray-finned fishes is lacking, much progress towards a phylogenetic synthesis has been achieved by cladistic analysis of morphological characters of living and fossil taxa. In contrast, molecular systematic studies among major groups of ray-finned fishes have not kept pace with morphological studies. This project involves a large-scale effort to develop suitable molecular markers for higher-level systematics and to compile a large data set of DNA sequences for candidate nuclear genes, for at least 150 representative fish taxa. At the same time, an alternative strategy is also proposed whereby ten carefully selected fish mitochondrial genomes will be sequenced and phylogenetically compared to published sequences that already include 13 complete mitochondrial genomes of sharks and rays, lungfish, and other actinopterygians. The data generated by these two approaches will be used to study phylogenetic relationships among the major groups of ray-finned fishes and to improve our understanding of the major evolutionary transitions in the radiation of fishes. The existing morphological information will be brought together with the new molecular data for analysis. The research proposed should establish a sound framework of reference for future phylogenetic studies of fishes. The goal of the educational component of the project is to develop an integrated program in systematics in general with emphases in vertebrate zoology and molecular systematics, to enhance undergraduate and graduate learning of evolutionary biology. A new five-week, hands-on laboratory course on molecular techniques for ecology and evolution will be developed. Application of both established and innovative teaching resources are proposed as a means to enhance student involvement in the learning process. Active participation in cooperative learning groups, exploration and analysis of WWW resources, and critical evaluation of the primary literature are some of the proposed activities to complement more traditional teaching practices. Web sites for the courses are an integral part to achieving these goals. The tight relationship between active research and the learning process will be emphasized throughout, steadily pursuing promising answers rather than final truths.