Geographic Variation, Speciation and Clines
eBook - PDF

Geographic Variation, Speciation and Clines

  1. English
  2. PDF
  3. Available on iOS & Android
eBook - PDF

Geographic Variation, Speciation and Clines

About this book

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.

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Yes, you can access Geographic Variation, Speciation and Clines by John A. Endler in PDF and/or ePUB format, as well as other popular books in Biological Sciences & Ecology. We have over one million books available in our catalogue for you to explore.

Table of contents

  1. Cover Page
  2. Half-title Page
  3. Title Page
  4. Copyright Page
  5. Dedication
  6. Preface
  7. Contents
  8. 1. Introductions
  9. 2. On gene flow
  10. 3. Properties of clines
  11. 4. Experimental clines and the effects of interaction among different loci
  12. 5. Parapatric speciation
  13. 6. Secondary or primary intergradation?
  14. Glossary
  15. Literature Cited
  16. Subject Index
  17. Author Index