Fisheries genetics researchers will find invaluable the thirty-eight peer-reviewed contributions in this book, presented at the 20th Lowell Wakefield Fisheries Symposium "Genetics of Subpolar Fish and Invertebrates," held in May 2002 in Juneau, Alaska. Looming over concerns of lost fisheries stocks and persistent erosion of genetic variability are predictions of global warming, which may further tax genetic resources. One consequence is an increased reliance on genetic applications to many aspects of fisheries management, aquaculture, and conservation. The contributions in this book are important to modern fisheries science and genetics, and illustrate the evolution of the field over the past decade. The improved technology provides tools to address increasingly complicated problems in traditional applications and ecological and behavioral studies. The union between molecular and quantitative genetics, where many of the major questions about population structure and evolution remain unanswered, will also benefit from the new technologies.

From a global perspective aquaculture is an activity related to food production with large potential for growth. Considering a continuously growing population, the efficiency and sustainability of this activity will be crucial to meet the needs of protein for human consumption in the near future. However, for continuous enhancement of the culture of both fish and shellfish there are still challenges to overcome, mostly related to the biology of the cultured species and their interaction with (increasingly changing) environmental factors. Examples of these challenges include early sexual maturation, feed meal replacement, immune response to infectious diseases and parasites, and temperature and salinity tolerance. Moreover, it is estimated that less than 10% of the total aquaculture production in the world is based on populations genetically improved by means of artificial selection. Thus, there is considerable room for implementing breeding schemes aimed at improving productive traits having significant economic impact. By far the most economically relevant trait is growth rate, which can be efficiently improved by conventional genetic selection (i.e. based on breeding values of selection candidates). However, there are other important traits that cannot be measured directly on selection candidates, such as resistance against infectious and parasitic agents and carcass quality traits (e.g. fillet yield and meat color). However, these traits can be more efficiently improved using molecular tools to assist breeding programs by means of marker-assisted selection, using a few markers explaining a high proportion of the trait variation, or genomic selection, using thousands of markers to estimate genomic breeding values. The development and implementation of new technologies applied to molecular biology and genomics, such as next-generation sequencing methods and high-throughput genotyping platforms, are allowing the rapid increase of availability of genomic resources in aquaculture species. These resources will provide powerful tools to the research community and will aid in the determination of the genetic factors involved in several biological aspects of aquaculture species. In this regard, it is important to establish discussion in terms of which strategies will be more efficient to solve the primary challenges that are affecting aquaculture systems around the world. The main objective of this Research Topic is to provide a forum to communicate recent research and implementation strategies in the use of genomics in aquaculture species with emphasis on (1) a better understanding of fish and shellfish biological processes having considerable impact on aquaculture systems; and (2) the efficient incorporation of molecular information into breeding programs to accelerate genetic progress of economically relevant traits.

This volume presents provocative research in four broad areas: Evolution of Life and Evolutionary Theory, including papers on the origin of life, stress and evolution; Genome Evolution, including papers on adaptive genome regulation, and comparative mammalian genomes; Phylogeography and Phylogeny, including papers on mushroom phylogeny, macroevolution, and the origin of higher taxa; Human Evolution and Ecology, including papers on man's place in nature, and the origin of human hairlessness.

The basic principle of all molecular genetic methods is to employ inherited, discrete and stable markers to identify genotypes that characterize individuals, populations or species. Such genetic data can provide information ori the levels and distribution of genetic variability in relation to mating patterns, life history, population size, migration and environment. Although molecular tools have long been employed to address various questions in fisheries biology and management, their contributions to the field are sometimes unclear, and often controversial. Much of the initial impetus for the deployment of molecular markers arose from the desire to assess fish stock structure based on various interpretations of the stock concept. Although such studies have met with varying success, they continue to provide an impetus for the development of increasingly sensitive population discriminators, yielding information that can be valuable for both sustainable exploitation and the conservation of fish populations. In the last major synthesis of the subject, Ryman and Utter (1987) summarized progress and applications, though this was prior to the wide-scale adoption of DNA methodology. New sources of genetic markers and protocols are now available, in particular those that exploit the widely distributed and highly variable repeat sequences of DNA, and the amplification technique of the polymerase chain reaction.

Sequenced biological macromolecules have revitalized systematic studies of evolutionary history. Molecular Systematics of Fishes is the first authoritative overview of the theory and application of these sequencing data to fishes. This volume explores the phylogeny of fishes at multiple taxonomic levels, uses methods of analysis of molecular data that apply both within and between fish populations, and employs molecule-based phylogenies to address broader questions of evolution. Targeted readers include ichthyologists, marine scientists, and all students, faculty, and researchers interested in fish evolution and ecology and vertebrate systematics. - Focuses on the phylogeny and evolutionary biology of fishes - Contains phylogenies of fishes at multiple taxonomic levels - Applies molecule-based phylogenies to broader questions of evolution - Includes methods for critique of analysis of molecular data

International Workshop on Marine Genetics - Rio 98