Island Life; Or, The Phenomena and Causes of Insular Faunas and Floras. Alfred Russel Wallace

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СКАЧАТЬ href="#ulink_f2c415b2-549a-5a0a-be2b-ad6b8605a1f9">CHAPTER XVII

       CHAPTER XVIII

       CHAPTER XIX

       CHAPTER XX

       CHAPTER XXI

       CHAPTER XXII

       CHAPTER XXIII

       CHAPTER XXIV

PART I

       Table of Contents

      THE DISPERSAL OF ORGANISMS; ITS PHENOMENA, LAWS, AND CAUSES

CHAPTER I

       Table of Contents

      INTRODUCTORY

      Remarkable Contrasts in the Distribution of Animals—Britain and Japan—Australia and New Zealand—Bali and Lombok—Florida and Bahama Islands—Brazil and Africa—Borneo, Madagascar, and Celebes—Problems in Distribution to be found in every Country—Can be Solved only by the Combination of many distinct lines of inquiry, Biological and Physical—Islands offer the best Subjects for the Study of Distribution—Outline of the Subjects to be discussed in the Present Volume.

      Pages 3-11

CHAPTER II

       Table of Contents

      THE ELEMENTARY FACTS OF DISTRIBUTION.

      Importance of Locality as an Essential Character of Species—Areas of Distribution—Extent and Limitations of Specific Areas—Specific Range of Birds—Generic Areas—Separate and Overlapping Areas—The Species of Tits as illustrating Areas of Distribution—The Distribution of the Species of Jays—Discontinuous Generic Areas—Peculiarities of Generic and Family Distribution—General Features of Overlapping and Discontinuous Areas—Restricted Areas of Families—The Distribution of Orders

      Pages 12-30

CHAPTER III

       Table of Contents

      CLASSIFICATION OF THE FACTS OF DISTRIBUTION.—ZOOLOGICAL REGIONS

      The Geographical Divisions of the Globe do not Correspond to Zoological Divisions—The Range of British Mammals as Indicating a Zoological Region—Range of East Asian and North African Mammals—The Range of British Birds—Range of East Asian Birds—The Limits of the Palæarctic Region—Characteristic Features of the Palæarctic Region—Definition and Characteristic Groups of the Ethiopian Region—Of the Oriental Region—Of the Australian Region—Of the Nearctic Region—Of the Neotropical Region—Comparison of Zoological Regions with the Geographical Divisions of the Globe

      Pages 31-54

CHAPTER IV

       Table of Contents

      EVOLUTION AS THE KEY TO DISTRIBUTION

      Importance of the Doctrine of Evolution—The Origin of New Species—Variation in Animals—The amount of Variation in North American Birds—How New Species Arise from a Variable Species—Definition and Origin of Genera—Cause of the Extinction of Species—The Rise and Decay of Species and Genera—Discontinuous Specific Areas, why Rare—Discontinuity of the Area of Parus Palustris—Discontinuity of Emberiza Schœniclus—The European and Japanese Jays—Supposed examples of Discontinuity among North American Birds—Distribution and Antiquity of Families—Discontinuity a Proof of Antiquity—Concluding remarks

      Pages 55-71

CHAPTER V

       Table of Contents

      THE POWERS OF DISPERSAL OF ANIMALS AND PLANTS

      Statement of the General Question of Dispersal—The Ocean as a Barrier to the Dispersal of Mammals—The Dispersal of Birds—The Dispersal of Reptiles—The Dispersal of Insects—The Dispersal of Land Mollusca—Great Antiquity of Land-shells—Causes Favouring the Abundance of Land-shells—The Dispersal of Plants—Special Adaptability of Seeds for Dispersal—Birds as Agents in the Dispersal of Seeds—Ocean Currents as Agents in Plant Dispersal—Dispersal along Mountain Chains—Antiquity of Plants as Effecting their Distribution

      Pages 72-82

CHAPTER VI

       Table of Contents

      GEOGRAPHICAL AND GEOLOGICAL CHANGES: THE PERMANENCE OF CONTINENTS

      Changes of Land and Sea, their Nature and Extent—Shore-Deposits and Stratified Rocks—The Movements of Continents—Supposed Oceanic Formations; the Origin of Chalk—Fresh-water and Shore-deposits as Proving the Permanence of Continents—Oceanic Islands as Indications of the Permanence of Continents and Oceans—General Stability of Continents with Constant Change of Form—Effect of Continental Changes on the Distribution of Animals—Changed Distribution Proved by the Extinct Animals of Different Epochs—Summary of Evidence for the General Permanence of Continents and Oceans.

      Pages 83-105

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