John A. Endler – författare

This volume brings together evidence that animal behaviour varies geograhically, and explores some of the richness in phenomena, interpretations, and problems which can arise in such studies. The authors summarize advances in the field to date, evaluate the strengths and weaknesses of various approaches, and give a clear and balanced overview of this area.

Two of the great mysteries of biology yet to be explored concern the distribution and abundance of genetic variation in natural populations and the genetic architecture of complex traits. These are tied together by their relationship to natural selection and evolutionary history, and some of the keys to disclosing these secrets lie in the study of wild organisms in their natural environments.This book, featuring a superb selection of papers from leading authors, summarizes the state of current understanding about the extent of genetic variation within wild populations and the ways to monitor such variation. It proposes the idea that a fundamental objective of evolutionary ecology is necessary to predict organism, population, community, and ecosystem response to environmental change. In fact, the overall theme of the papers centers around the expression of genetic variation and how it is shaped by the action of natural selection in the natural environment.Patterns of adaptation in the past and the genetic basis of traits likely to be under selection in a dynamically changing environment is discussed along with a wide variety of techniques to test for genetic variation and its consequences, ranging from classical demography to the use of molecular markers. This book is perfect for professionals and graduate students in genetics, biology, ecology, conservation biology, and evolution.

Geographic Variation, Speciation and Clines explores the origins and development of geographic variation, divergence, and speciation. In particular it is concerned with genetic divergence as it is usually found on continents, among groups of populations isolated only by distance. Although earlier writers on this topic considered the effects of geography and dispersal, intense geographic differentiation and speciation were thought to require complete isolation. Professor Endler shows how geographic differentiation and speciation may develop in spite of continuous gene flow. Following a review of the diverse and scattered literature on gene flow and population differentiation, the author discusses the relationships among gene flow, dispersal, and migration. He then summarizes the factors which limit the geographic extent of gene flow, and those which allow steep clines to develop in the absence of barriers to gene flow. His analysis draws on examples from the field, experiments, and single- and multiple-locus models. The mechanism and conditions for parapatric speciation are presented: steepening clines, development into hybrid zones, and the evolution of sexual isolation.In the final chapter the author considers the interpretation of natural clines and the associated geographic patterns of subspecies and species.