From guppies to Galapagos finches and from adaptive landscapes to haldanes, this compilation of contributed works provides reviews, perspectives, theoretical models, statistical developments, and empirical demonstrations exploring the tempo and mode of microevolution on contemporary to geological time scales. New developments, and reviews, of classic and novel empirical systems demonstrate the strength and diversity of evolutionary processes producing biodiversity within species. Perspectives and theoretical insights expand these empirical observations to explore patterns and mechanisms of microevolution, methods for its quantification, and implications for the evolution of biodiversity on other scales. This diverse assemblage of manuscripts is aimed at professionals, graduate students, and advanced undergraduates who desire a timely synthesis of current knowledge, an illustration of exciting new directions, and a springboard for future investigations in the study of microevolution in the wild.
Many of the processes influencing recruitment to an adult fish population or entry into a fishery occur very early in life. The variations in life histories and behaviours of young fish and the selective processes operating on this variation ultimately determine the identities and abundance of survivors. This important volume brings together contributions from many of the world's leading researchers from the field of fish ecology. The book focuses on three major themes of pressing importance in the analysis of the role that the early life history of fishes plays in the number and quality of recruits: the selective processes at play in their early life history; the contributions of early life history to the understanding of recruitment.
The system of the Tigris-Euphrates Rivers is one of the great river systems of southwestern Asia. It comprises the Tigris and Euphrates Rivers, which follow roughly parallel courses through the heart of the Middle East. The lower portion of the region that they run through is known as Mesopotamia, was one of the cradles of civilisation. There are several environmental factors that govern the nature of the two rivers and shape the landscape the two rivers running through. Geological events create rivers, climate monitor the water supply, the surrounding land influences the vegetation and the physical and chemical features of water. The Tigris-Euphrates system runs through the territory of four countries, Iraq, Iran, Turkey and Syria. Therefore, any scientific approach to the environment of these two rivers should include the natural history events in these countries. The book "Tigris and Euphrates Rivers: Their Environment from Headwaters to Mouth" will be divided into nine parts. These parts deal with the issues of the environment, the status of the flora and fauna, the abiotic aspects, ecology, hydrological regime of the two rivers, the biotic aspects. Water resources, stress of the environment, conservation issues. Since the book of Julian Rzoska "Euphrates and Tigris Mesopotamian Ecology and Destiny" in 1980, no book or major reference has been published that includes between its cover the facts and information that the present book will present. Therefore, the importance of the present book falls in stating the present status of the environment of the two rivers and the comparison of their environment between now and that of 37 years ago as given by J. Rzoska (1980). The recent studies showed that there are a large number of natural and political events that happened within the last three decades in the area of the Tigris-Euphrates river system that for sure have done a great change to the environment of the two rivers and consequently changing the biological and non-biological resources of the two rivers. This book will be a reference book to both Academic and students across the Middle East in different disciplines of knowledge to use in their researches on Tigris-Euphrates river system. The scholars interested in this area will use this book as a guide to compare this freshwater system with other areas in Asia and the world.
As salmonids have been reared for more than a century in many countries, one might expect that principles are well established and provide a solid foundation for salmonid aquaculture. Indeed, some of the methods used today in salmonid rearing are nearly identical to those employed one hundred years ago. Areas of salmonid research today include nutrition, smolt and stress physiology, genetics and biotechnology.The purpose of this book is to provide a useful synthesis of the biology and culture of salmonid fishes. The important practices in salmonid culture as well as the theory behind them is described. This volume will be of interest to students, researchers, fisheries biologists and managers as well as practising aquaculturists.
Atlantic salmon (Salmo salar, L) is an anadromous species contributing to major fishery catches and comprising a significant part of the aquaculturally produced fish for human consumption. The aim of this book is to incite the interest in the field of knowledge gathered from a broad scope of disciplines that have investigated this fish species. Und
Because of the pervasive and substantial decline of Atlantic salmon populations in Maine over the past 150 years, and because they are close to extinction, a comprehensive statewide action should be taken now to ensure their survival. The populations of Atlantic salmon have declined drastically, from an estimated half million adult salmon returning to U.S. rivers each year in the early 1800s to perhaps as few as 1,000 in 2001. The report recommends implementing a formalized decision-making approach to establish priorities, evaluate options and coordinate plans for conserving and restoring the salmon.