Chapter I: Preface

When studying the Warblers some twenty years ago, I became aware of the fact that each male isolates itself at the commencement of the breeding season and exercises dominion over a restricted area of ground. Further investigation, pursued with a view to ascertaining the relation of this particular mode of behaviour to the system of reproduction, led to my studying various species, not only those of close affinity, but those widely remote in the tree of avian life. The present work is the outcome of those investigations. In it I have endeavoured to interpret the prospective value of the behaviour, and to trace out the relationships in the organic and inorganic world which have determined its survival. Much is mere speculation; much with fuller knowledge may be found to be wrong. But I venture to hope that a nucleus will remain upon which a more complete territorial system may one day be established.

I have to thank Mr. G. E. Lodge and Mr. H. Grönvold for the trouble they have taken in executing my wishes; I also want to record my indebtedness to the late E. W. Hopewell; and to Professor Lloyd Morgan, F.R.S., I am beholden more than I can tell.

CONTENTS

PAGE
CHAPTER I

INTRODUCTION 1

CHAPTER II

THE DISPOSITION TO SECURE A TERRITORY 20

CHAPTER III

THE DISPOSITION TO DEFEND THE TERRITORY 73

CHAPTER IV

THE RELATION OF SONG TO THE TERRITORY 119

CHAPTER V

THE RELATION OF THE TERRITORY TO THE SYSTEM
OF REPRODUCTION 169

CHAPTER VI

THE WARFARE BETWEEN DIFFERENT SPECIES AND ITS
RELATION TO THE TERRITORY 216