Chapter I: Front Matter

FOOTNOTES:

A NATURALIST'S VOYAGE ROUND THE WORLD By Charles Darwin, M.A., F.R.S.

First Edition May 1860 Second Edition May 1870 Third Edition February 1872 Fourth Edition July 1874 Fifth Edition March 1876 Sixth Edition January 1879 Seventh Edition May 1882 Eighth Edition February 1884 Ninth Edition August 1886 Tenth Edition January 1888 Eleventh Edition January 1890 Reprinted June 1913

INDEX LIST OF ILLUSTRATIONS

CONTENTS Chapter I

Porto Praya — Ribeira Grande — Atmospheric Dust with Infusoria — Habits of a Sea-slug and Cuttle-fish — St. Paul's Rocks, non-volcanic — Singular Incrustations — Insects the first Colonists of Islands — Fernando Noronha — Bahia — Burnished Rocks — Habits of a Diodon — Pelagic Confervæ and Infusoria — Causes of discoloured Sea. Chapter II

Rio de Janeiro — Excursion north of Cape Frio — Great Evaporation — Slavery — Botofogo Bay — Terrestrial Planariae — Clouds on the Corcovado — Heavy Rain — Musical Frogs — Phosphorescent insects — Elater, springing powers of — Blue Haze — Noise made by a Butterfly — Entomology — Ants — Wasp killing a Spider — Parasitical Spider — Artifices of an Epeira — Gregarious Spider — Spider with an unsymmetrical web. Chapter III

Monte Video — Maldonado — Excursion to R. Polanco — Lazo and Bolas — Partridges — Absence of trees — Deer — Capybara, or River Hog — Tucutuco — Molothrus, cuckoo-like habits — Tyrant-flycatcher — Mocking-bird — Carrion Hawks — Tubes formed by lightning — House struck. Chapter IV

Rio Negro — Estancias attacked by the Indians — Salt-Lakes — Flamingoes — R. Negro to R. Colorado — Sacred Tree — Patagonian Hare — Indian Families — General Rosas — Proceed to Bahia Blanca — Sand Dunes — Negro Lieutenant — Bahia Blanca — Saline incrustations — Punta Alta — Zorillo. Chapter V

Bahia Blanca — Geology — Numerous gigantic extinct Quadrupeds — Recent Extinction — Longevity of Species — Large Animals do not require a luxuriant vegetation — Southern Africa — Siberian Fossils — Two Species of Ostrich — Habits of Oven-bird — Armadilloes — Venomous Snake, Toad, Lizard — Hybernation of Animals — Habits of Sea-Pen — Indian Wars and Massacres — Arrowhead — Antiquarian Relic. Chapter VI

Set out for Buenos Ayres — Rio Sauce — Sierra Ventana — Third Posta — Driving Horses — Bolas — Partridges and Foxes — Features of the country — Long-legged Plover — Teru-tero — Hail-storm — Natural enclosures in the Sierra Tapalguen — Flesh of Puma — Meat Diet — Guardia del Monte — Effects of cattle on the Vegetation — Cardoon — Buenos Ayres — Corral where cattle are slaughtered. Chapter VII

Excursion to St. Fé — Thistle Beds — Habits of the Bizcacha — Little Owl — Saline streams — Level plains — Mastodon — St. Fé — Change in landscape — Geology — Tooth of extinct Horse — Relation of the Fossil and recent Quadrupeds of North and South America — Effects of a great drought — Parana — Habits of the Jaguar — Scissor-beak — Kingfisher, Parrot, and Scissor-tail — Revolution — Buenos Ayres — State of Government. Chapter VIII

Excursion to Colonia del Sacramiento — Value of an Estancia — Cattle, how counted — Singular breed of Oxen — Perforated pebbles — Shepherd-dogs — Horses broken-in, Gauchos riding — Character of Inhabitants — Rio Plata — Flocks of Butterflies — Aeronaut Spiders — Phosphorescence of the Sea — Port Desire — Guanaco — Port St. Julian — Geology of Patagonia — Fossil gigantic Animal — Types of Organisation constant — Change in the Zoology of America — Causes of Extinction. Chapter IX

Santa Cruz — Expedition up the River — Indians — Immense streams of basaltic lava — Fragments not transported by the river — Excavation of the valley — Condor, habits of — Cordillera — Erratic boulders of great size — Indian relics — Return to the ship — Falkland Islands — Wild horses, cattle, rabbits — Wolf-like fox — Fire made of bones — Manner of hunting wild cattle — Geology — Streams of stones — Scenes of violence — Penguin — Geese — Eggs of Doris — Compound animals. Chapter X

Tierra del Fuego, first arrival — Good Success Bay — An account of the Fuegians on board — Interview with the savages — Scenery of the forests — Cape Horn — Wigwam Cove — Miserable condition of the savages — Famines — Cannibals — Matricide — Religious feelings — Great Gale — Beagle Channel — Ponsonby Sound — Build wigwams and settle the Fuegians — Bifurcation of the Beagle Channel — Glaciers — Return to the Ship — Second visit in the Ship to the Settlement — Equality of condition amongst the natives. Chapter XI

Strait of Magellan — Port Famine — Ascent of Mount Tarn — Forests — Edible fungus — Zoology — Great Seaweed — Leave Tierra del Fuego — Climate — Fruit-trees and productions of the southern coasts — Height of snow-line on the Cordillera — Descent of glaciers to the sea — Icebergs formed — Transportal of boulders — Climate and productions of the Antarctic Islands — Preservation of frozen carcasses — Recapitulation. Chapter XII

Valparaiso — Excursion to the foot of the Andes — Structure of the land — Ascend the Bell of Quillota — Shattered masses of greenstone — Immense valleys — Mines — State of miners — Santiago — Hot-baths of Cauquenes — Gold-mines — Grinding-mills — Perforated stones — Habits of the Puma — El Turco and Tapacolo — Humming-birds. Chapter XIII

Chiloe — General aspect — Boat excursion — Native Indians — Castro — Tame fox — Ascend San Pedro — Chonos Archipelago — Peninsula of Tres Montes — Granitic range — Boat-wrecked sailors — Low's Harbour — Wild potato — Formation of peat — Myopotamus, otter and mice — Cheucau and Barking-bird — Opetiorhynchus — Singular character of ornithology — Petrels. Chapter XIV

San Carlos, Chiloe — Osorno in eruption, contemporaneously with Aconcagua and Coseguina — Ride to Cucao — Impenetrable forests — Valdivia — Indians — Earthquake — Concepcion — Great earthquake — Rocks fissured — Appearance of the former towns — The sea black and boiling — Direction of the vibrations — Stones twisted round — Great Wave — Permanent Elevation of the land — Area of volcanic phenomena — The connection between the elevatory and eruptive forces — Cause of earthquakes — Slow elevation of mountain-chains. Chapter XV

Valparaiso — Portillo Pass — Sagacity of mules — Mountain-torrents — Mines, how discovered — Proofs of the gradual elevation of the Cordillera — Effect of snow on rocks — Geological structure of the two main ranges, their distinct origin and upheaval — Great subsidence — Red snow — Winds — Pinnacles of snow — Dry and clear atmosphere — Electricity — Pampas — Zoology of the opposite sides of the Andes — Locusts — Great Bugs — Mendoza — Uspallata Pass — Silicified trees buried as they grew — Incas Bridge — Badness of the passes exaggerated — Cumbre — Casuchas — Valparaiso. Chapter XVI

Coast-road to Coquimbo — Great loads carried by the miners — Coquimbo — Earthquake — Step-formed terraces — Absence of recent deposits — Contemporaneousness of the Tertiary formations — Excursion up the valley — Road to Guasco — Deserts — Valley of Copiapó — Rain and Earthquakes — Hydrophobia — The Despoblado — Indian ruins — Probable change of climate — River-bed arched by an earthquake — Cold gales of wind — Noises from a hill — Iquique — Salt alluvium — Nitrate of soda — Lima — Unhealthy country — Ruins of Callao, overthrown by an earthquake — Recent subsidence — Elevated shells on San Lorenzo, their decomposition — Plain with embedded shells and fragments of pottery — Antiquity of the Indian Race. Chapter XVII

Galapagos Archipelago — The whole group volcanic — Number of craters — Leafless bushes — Colony at Charles Island — James Island — Salt-lake in crater — Natural history of the group — Ornithology, curious finches — Reptiles — Great tortoises, habits of — Marine lizard, feeds on seaweed — Terrestrial lizard, burrowing habits, herbivorous — Importance of reptiles in the Archipelago — Fish, shells, insects — Botany — American type of organisation — Differences in the species or races on different islands — Tameness of the birds — Fear of man an acquired instinct. Chapter XVIII

Pass through the Low Archipelago — Tahiti — Aspect — Vegetation on the mountains — View of Eimeo — Excursion into the interior — Profound ravines — Succession of waterfalls — Number of wild useful plants — Temperance of the inhabitants — Their moral state — Parliament convened — New Zealand — Bay of Islands — Hippahs — Excursion to Waimate — Missionary establishment — English weeds now run wild — Waiomio — Funeral of a New Zealand woman — Sail for Australia. Chapter XIX

Sydney — Excursion to Bathurst — Aspect of the woods — Party of natives — Gradual extinction of the aborigines — Infection generated by associated men in health — Blue Mountains — View of the grand gulf-like valleys — Their origin and formation — Bathurst, general civility of the lower orders — State of Society — Van Diemen's Land — Hobart Town — Aborigines all banished — Mount Wellington — King George's Sound — Cheerless aspect of the country — Bald Head, calcareous casts of branches of trees — Party of natives — Leave Australia. Chapter XX

Keeling Island — Singular appearance — Scanty Flora — Transport of seeds — Birds and insects — Ebbing and flowing springs — Fields of dead coral — Stones transported in the roots of trees — Great crab — Stinging corals — Coral-eating fish — Coral formations — Lagoon islands or atolls — Depth at which reef-building corals can live — Vast areas interspersed with low coral islands — Subsidence of their foundations — Barrier-reefs — Fringing-reefs — Conversion of fringing-reefs into barrier-reefs, and into atolls — Evidence of changes in level — Breaches in barrier-reefs — Maldiva atolls, their peculiar structure — Dead and submerged reefs — Areas of subsidence and elevation — Distribution of volcanoes — Subsidence slow and vast in amount. Chapter XXI

Mauritius, beautiful appearance of — Great crateriform ring of mountains — Hindoos — St. Helena — History of the changes in the vegetation — Cause of the extinction of land-shells — Ascension — Variation in the imported rats — Volcanic bombs — Beds of infusoria — Bahia, Brazil — Splendour of tropical scenery — Pernambuco — Singular reefs — Slavery — Return to England — Retrospect on our voyage.

INDEX LIST OF ILLUSTRATIONS

THE FOUNDATIONS OF THE ORIGIN OF SPECIES TWO ESSAYS WRITTEN IN 1842 AND 1844 By Charles Darwin Edited By His Son Francis Darwin 1909 CONTENTS

ESSAY OF 1842

PAGES
Introduction xi

PART I

§ i. On variation under domestication, and on the principles of selection 1
§ ii. On variation in a state of nature and on the natural means of selection 4
§ iii. On variation in instincts and other mental attributes 17

PART II

§§ iv. and v. On the evidence from Geology. (The reasons for combining the two sections are given in the Introduction) 22
§ vi. Geographical distribution 29
§ vii. Affinities and classification 35
§ viii. Unity of type in the great classes 38
§ ix. Abortive organs 45
§ x. Recapitulation and conclusion 48

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ESSAY OF 1844

PART I

CHAPTER I ON THE VARIATION OF ORGANIC BEINGS UNDER DOMESTICATION; AND ON THE PRINCIPLES OF SELECTION.

Variation
On the hereditary tendency
Causes of Variation
On Selection
Crossing Breeds
Whether our domestic races have descended from one or more wild stocks
Limits to Variation in degree and kind
In what consists Domestication
Summary 57-80

CHAPTER II ON THE VARIATION OF ORGANIC BEINGS IN A WILD STATE; ON THE NATURAL MEANS OF SELECTION; AND ON THE COMPARISON OF DOMESTIC RACES AND TRUE SPECIES.

Variation
Natural means of Selection
Differences between “Races” and “Species”:—first, in their trueness or variability
Difference between “Races” and “Species” in fertility when crossed
Causes of Sterility in Hybrids
Infertility from causes distinct from hybridisation
Points of Resemblance between “Races” and “Species”
External characters of Hybrids and Mongrels
Summary
Limits of Variation 81-111

CHAPTER III ON THE VARIATION OF INSTINCTS AND OTHER MENTAL ATTRIBUTES UNDER DOMESTICATION AND IN A STATE OF NATURE; ON THE DIFFICULTIES IN THIS SUBJECT; AND ON ANALOGOUS DIFFICULTIES WITH RESPECT TO CORPOREAL STRUCTURES.

Variation of mental attributes under domestication
Hereditary habits compared with instincts
Variation in the mental attributes of wild animals
Principles of Selection applicable to instincts
Difficulties in the acquirement of complex instincts by Selection
Difficulties in the acquirement by Selection of complex corporeal structures 112-132

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PART II ON THE EVIDENCE FAVOURABLE AND OPPOSED TO THE VIEW THAT SPECIES ARE NATURALLY FORMED RACES, DESCENDED FROM COMMON STOCKS.

CHAPTER IV ON THE NUMBER OF INTERMEDIATE FORMS REQUIRED ON THE THEORY OF COMMON DESCENT; AND ON THEIR ABSENCE IN A FOSSIL STATE 133-143

CHAPTER V GRADUAL APPEARANCE AND DISAPPEARANCE OF SPECIES. 144-150

Gradual appearance of species
Extinction of species

CHAPTER VI ON THE GEOGRAPHICAL DISTRIBUTION OF ORGANIC BEINGS IN PAST AND PRESENT TIMES.

SECTION FIRST 151-174

Distribution of the inhabitants in the different continents
Relation of range in genera and species
Distribution of the inhabitants in the same continent
Insular Faunas
Alpine Floras
Cause of the similarity in the floras of some distant mountains
Whether the same species has been created more than once
On the number of species, and of the classes to which they belong in different regions

SECOND SECTION 174-182

Geographical distribution of extinct organisms
Changes in geographical distribution
Summary on the distribution of living and extinct organic beings

SECTION THIRD 183-197

An attempt to explain the foregoing laws of geographical distribution, on the theory of allied species having a common descent
Improbability of finding fossil forms intermediate between existing species

CHAPTER VII ON THE NATURE OF THE AFFINITIES AND CLASSIFICATION OF ORGANIC BEINGS. 198-213

Gradual appearance and disappearance of groups
What is the Natural System?
On the kind of relation between distinct groups
Classification of Races or Varieties
Classification of Races and Species similar
Origin of genera and families

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CHAPTER VIII UNITY OF TYPE IN THE GREAT CLASSES; AND MORPHOLOGICAL STRUCTURES.

Unity of Type
Morphology
Embryology
Attempt to explain the facts of embryology
On the graduated complexity in each great class
Modification by selection of the forms of immature animals
Importance of embryology in classification
Order in time in which the great classes have first appeared 214-230

CHAPTER IX ABORTIVE OR RUDIMENTARY ORGANS.

The abortive organs of Naturalists
The abortive organs of Physiologists
Abortion from gradual disuse 231-238

CHAPTER X RECAPITULATION AND CONCLUSION.

Recapitulation
Why do we wish to reject the Theory of Common Descent?
Conclusion 239-255
Index 257
Portrait frontispiece
Facsimile to face p. 50

ON THE ORIGIN OF SPECIES. OR THE PRESERVATION OF FAVOURED RACES IN THE STRUGGLE FOR LIFE. By Charles Darwin,

CONTENTS

DETEAILED CONTENTS.

ON THE ORIGIN OF SPECIES.

INTRODUCTION. 1. VARIATION UNDER DOMESTICATION. 2. VARIATION UNDER NATURE. 3. STRUGGLE FOR EXISTENCE. 4. NATURAL SELECTION 5. LAWS OF VARIATION. 6. DIFFICULTIES ON THEORY. 7. INSTINCT. 8. HYBRIDISM. 9. ON THE IMPERFECTION OF THE GEOLOGICAL RECORD. 10. ON THE GEOLOGICAL SUCCESSION OF ORGANIC BEINGS. 11. GEOGRAPHICAL DISTRIBUTION. 12. GEOGRAPHICAL DISTRIBUTION—continued. 13. MUTUAL AFFINITIES OF ORGANIC BEINGS: MORPHOLOGY: 14. RECAPITULATION AND CONCLUSION.

ON THE ORIGIN OF SPECIES BY MEANS OF NATURAL SELECTION, OR THE PRESERVATION OF FAVOURED RACES IN THE STRUGGLE FOR LIFE By CHARLES DARWIN CONTENTS. INDEX

INTRODUCTION

Page 1 CHAPTER I.

Variation under Domestication.

Causes of Variability—Effects of Habit—Correlation of Growth—Inheritance—Character of Domestic Varieties—Difficulty of distinguishing between Varieties and Species—Origin of Domestic Varieties from one or more Species—Domestic Pigeons, their Differences and Origin—Principle of Selection anciently followed, its Effects—Methodical and Unconscious Selection—Unknown Origin of our Domestic Productions—Circumstances favourable to Man's power of Selection

7-43 CHAPTER II.

Variation under Nature.

Variability—Individual differences—Doubtful species—Wide ranging, much diffused, and common species vary most—Species of the larger genera in any country vary more than the species of the smaller genera—Many of the species of the larger genera resemble varieties in being very closely, but unequally, related to each other, and in having restricted ranges

44-59 CHAPTER III.

Struggle for Existence.

Its bearing on natural selection—The term used in a wide sense—Geometrical powers of increase—Rapid increase of naturalised animals and plants—Nature of the checks to increase—Competition universal—Effects of climate—Protection from the number of individuals—Complex relations of all animals and plants throughout nature—Struggle for life most severe between individuals and varieties of the same species; often severe between species of the same genus—The relation of organism to organism the most important of all relations

60-79 CHAPTER IV.

Natural Selection.

Natural Selection—its power compared with man's selection—its power on characters of trifling importance—its power at all ages and on both sexes—Sexual Selection—On the generality of intercrosses between individuals of the same species—Circumstances favourable and unfavourable to Natural Selection, namely, intercrossing, isolation, number of individuals—Slow action—Extinction caused by Natural Selection—Divergence of Character, related to the diversity of inhabitants of any small area, and to naturalisation—Action of Natural Selection, through Divergence of Character and Extinction, on the descendants from a common parent—Explains the Grouping of all organic beings

80-130 CHAPTER V.

Laws of Variation.

Effects of external conditions—Use and disuse, combined with natural selection; organs of flight and of vision—Acclimatisation—Correlation of growth—Compensation and economy of growth—False correlations—Multiple, rudimentary, and lowly organised structures variable—Parts developed in an unusual manner are highly variable: specific characters more variable than generic: secondary sexual characters variable—Species of the same genus vary in an analogous manner—Reversions to long-lost characters—Summary

131-170 CHAPTER VI.

Difficulties on Theory.

Difficulties on the theory of descent with modification—Transitions—Absence or rarity of transitional varieties—Transitions in habits of life—Diversified habits in the same species—Species with habits widely different from those of their allies—Organs of extreme perfection—Means of transition—Cases of difficulty—Natura non facit saltum—Organs of small importance—Organs not in all cases absolutely perfect—The law of Unity of Type and of the Conditions of Existence embraced by the theory of Natural Selection

171-206 CHAPTER VII.

Instinct.

Instincts comparable with habits, but different in their origin—Instincts graduated—Aphides and ants—Instincts variable—Domestic instincts, their origin—Natural instincts of the cuckoo, ostrich, and parasitic bees—Slave-making ants—Hive-bee, its cell-making instinct—Difficulties on the theory of the Natural Selection of instincts—Neuter or sterile insects—Summary

207-244 CHAPTER VIII.

Hybridism.

Distinction between the sterility of first crosses and of hybrids—Sterility various in degree, not universal, affected by close interbreeding, removed by domestication—Laws governing the sterility of hybrids—Sterility not a special endowment, but incidental on other differences—Causes of the sterility of first crosses and of hybrids—Parallelism between the effects of changed conditions of life and crossing—Fertility of varieties when crossed and of their mongrel offspring not universal—Hybrids and mongrels compared independently of their fertility—Summary

245-278 CHAPTER IX.

On the Imperfection of the Geological Record.

On the absence of intermediate varieties at the present day—On the nature of extinct intermediate varieties; on their number—On the vast lapse of time, as inferred from the rate of deposition and of denudation—On the poorness of our palæontological collections—On the intermittence of geological formations—On the absence of intermediate varieties in any one formation—On the sudden appearance of groups of species—On their sudden appearance in the lowest known fossiliferous strata

279-311 CHAPTER X.

On the Geological Succession of Organic Beings.

On the slow and successive appearance of new species—On their different rates of change—Species once lost do not reappear—Groups of species follow the same general rules in their appearance and disappearance as do single species—On Extinction—On simultaneous changes in the forms of life throughout the world—On the affinities of extinct species to each other and to living species—On the state of development of ancient forms—On the succession of the same types within the same areas—Summary of preceding and present chapters

312-345 CHAPTER XI.

Geographical Distribution.

Present distribution cannot be accounted for by differences in physical conditions—Importance of barriers—Affinity of the productions of the same continent—Centres of creation—Means of dispersal, by changes of climate and of the level of the land, and by occasional means—Dispersal during the Glacial period co-extensive with the world

346-382 CHAPTER XII.

Geographical Distribution—continued.

Distribution of fresh-water productions—On the inhabitants of oceanic islands—Absence of Batrachians and of terrestrial Mammals—On the relation of the inhabitants of islands to those of the nearest mainland—On colonisation from the nearest source with subsequent modification—Summary of the last and present chapters

383-410 CHAPTER XIII.

Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs.

Classification, groups subordinate to groups—Natural system—Rules and difficulties in classification, explained on the theory of descent with modification—Classification of varieties—Descent always used in classification—Analogical or adaptive characters—Affinities, general, complex and radiating—Extinction separates and defines groups—Morphology, between members of the same class, between parts of the same individual—Embryology, laws of, explained by variations not supervening at an early age, and being inherited at a corresponding age—Rudimentary organs; their origin explained—Summary

411-458 CHAPTER XIV.

Recapitulation and Conclusion.

Recapitulation of the difficulties on the theory of Natural Selection—Recapitulation of the general and special circumstances in its favour—Causes of the general belief in the immutability of species—How far the theory of natural selection may be extended—Effects of its adoption on the study of Natural history—Concluding remarks

459-490

THE ORIGIN OF SPECIES BY MEANS OF NATURAL SELECTION; OR THE PRESERVATION OF FAVOURED RACES IN THE STRUGGLE FOR LIFE. By Charles Darwin, M.A., F.R.S., Author of "The Descent of Man," etc., etc.

Sixth London Edition, with all Additions and Corrections. The 6th Edition is often considered the definitive edition.

CONTENTS AN HISTORICAL SKETCH OF THE PROGRESS OF OPINION ON THE ORIGIN OF SPECIES DETAILED CONTENTS ORIGIN OF SPECIES INTRODUCTION CHAPTER I VARIATION UNDER DOMESTICATION CHAPTER II VARIATION UNDER NATURE CHAPTER III STRUGGLE FOR EXISTENCE CHAPTER IV NATURAL SELECTION; OR THE SURVIVAL OF THE FITTEST CHAPTER V LAWS OF VARIATION CHAPTER VI DIFFICULTIES OF THE THEORY CHAPTER VII MISCELLANEOUS OBJECTIONS TO THE THEORY OF NATURAL SELECTION CHAPTER VIII INSTINCT CHAPTER IX HYBRIDISM CHAPTER X ON THE IMPERFECTION OF THE GEOLOGICAL RECORD CHAPTER XI. ON THE GEOLOGICAL SUCCESSION OF ORGANIC BEINGS CHAPTER XII GEOGRAPHICAL DISTRIBUTION CHAPTER XIII GEOGRAPHICAL DISTRIBUTION—continued CHAPTER XIV MUTUAL AFFINITIES OF ORGANIC BEINGS CHAPTER XV RECAPITULATION AND CONCLUSION GLOSSARY OF THE PRINCIPAL SCIENTIFIC TERMS USED IN THE PRESENT VOLUME INDEX

THE DESCENT OF MAN AND SELECTION IN RELATION TO SEX By Charles Darwin IN TWO VOLUMES—Vol. I. With Illustrations CONTENTS Introduction Page 1-5 PART I. ON THE DESCENT OF MAN CHAPTER I. The Evidence of the Descent of man from some Lower form. Nature of the evidence bearing on the origin of man—Homologous structures in man and the lower animals—Miscellaneous points of correspondence—Development—Rudimentary structures, muscles, sense-organs, hair, bones, reproductive organs, &c.—The bearing of these three great classes of facts on the origin of man 9-33 CHAPTER II. Comparison of the Mental Powers of Man and the Lower Animals. The difference in mental power between the highest ape and the lowest savage, immense—Certain instincts in common—The emotions—Curiosity—Imitation—Attention—Memory—Imagination—Reason—Progressive improvement—Tools and weapons used by animals—Language—Self-consciousness—Sense of beauty—Belief in God, spiritual agencies, superstitions 34-69 CHAPTER III. Comparison of the Mental Powers of Man and the Lower Animals—continued. The difference in mental power between the highest ape and the lowest savage, immense—Certain instincts in common—The emotions—Curiosity—Imitation—Attention—Memory—Imagination—Reason—Progressive improvement—Tools and weapons used by animals—Language—Self-consciousness—Sense of beauty—Belief in God, spiritual agencies, superstitions 70-106 CHAPTER IV. On the Manner of Development of Man from some Lower Form. Variability of body and mind in man—Inheritance—Causes of variability—Laws of variation the same in man as in the lower animals—Direct action of the conditions of life—Effects of the increased use and disuse of parts—Arrested development—Reversion—Correlated variation—Rate of increase—Checks to increase—Natural selection—Man the most dominant animal in the world—Importance of his corporeal structure—The causes which have led to his becoming erect—Consequent changes of structure—Decrease in size of the canine teeth—Increased size and altered shape of the skull—Nakedness—Absence of a tail—Defenceless condition of man 107-157 CHAPTER V. On the Development of the Intellectual and Moral Faculties during Primeval and Civilised Times. The advancement of the intellectual powers through natural selection—Importance of imitation—Social and moral faculties—Their development within the limits of the same tribe—Natural selection as affecting civilised nations—Evidence that civilised nations were once barbarous 158-184 CHAPTER VI. On the Affinities and Genealogy of Man. Position of man in the animal series—The natural system genealogical—Adaptive characters of slight value—Various small points of resemblance between man and the Quadrumana—Rank of man in the natural system—Birthplace and antiquity vii of man—Absence of fossil connecting-links—Lower stages in the genealogy of man, as inferred, firstly from his affinities and secondly from his structure—Early androgynous condition of the Vertebrata—Conclusion 185-213 CHAPTER VII. On the Races of Man. The nature and value of specific characters—Application to the races of man—Arguments in favour of, and opposed to, ranking the so-called races of man as distinct species—Sub-species—Monogenists and polygenists—Convergence of character—Numerous points of resemblance in body and mind between the most distinct races of man—The state of man when he first spread over the earth—Each race not descended from a single pair—The extinction of races—The formation of races—The effects of crossing—Slight influence of the direct action of the conditions of life—Slight or no influence of natural selection—Sexual selection. 214-250 PART II.

SEXUAL SELECTION. CHAPTER VIII. Principles of Sexual Selection. Secondary sexual characters—Sexual selection—Manner of action—Excess of males—Polygamy—The male alone generally modified through sexual selection—Eagerness of the male—Variability of the male—Choice exerted by the female—Sexual compared with natural selection—Inheritance at corresponding periods of life, at corresponding seasons of the year, and as limited by sex—Relations between the several forms of inheritance—Causes why one sex and the young are not modified through sexual selection—Supplement on the proportional numbers of the two sexes throughout the animal kingdom—On the limitation of the numbers of the two sexes through natural selection 253-320 CHAPTER IX. Secondary Sexual Characters in the Lower Classes of the Animal Kingdom. viii These characters absent in the lowest classes—Brilliant colours—Mollusca—Annelids—Crustacea, secondary sexual characters strongly developed; dimorphism; colour; characters not acquired before maturity—Spiders, sexual colours of; stridulation by the males—Myriapoda 321-340 CHAPTER X. Secondary Sexual Characters of Insects. Diversified structures possessed by the males for seizing the females—Differences between the sexes, of which the meaning is not understood—Difference in size between the sexes—Thysanura—Diptera—Hemiptera—Homoptera, musical powers possessed by the males alone—Orthoptera, musical instruments of the males, much diversified in structure; pugnacity; colours—Neuroptera, sexual differences in colour—Hymenoptera, pugnacity and colours—Coleoptera, colours; furnished with great horns, apparently as an ornament; battles; stridulating organs generally common to both sexes 341-385 CHAPTER XI. Insects, continued.—Order Lepidoptera. Courtship of butterflies—Battles—Ticking noise—Colours common to both sexes, or more brilliant in the males—Examples—Not due to the direct action of the conditions of life—Colours adapted for protection—Colours of moths—Display—Perceptive powers of the Lepidoptera—Variability—Causes of the difference in colour between the males and females—Mimickry, female butterflies more brilliantly coloured than the males—Bright colours of caterpillars—Summary and concluding remarks on the secondary sexual characters of insects—Birds and insects compared 386-423 FOOTNOTES

THE DESCENT OF MAN, AND SELECTION IN RELATION TO SEX By Charles Darwin IN TWO VOLUMES.-Vol. II. WITH ILLUSTRATIONS

CONTENTS FOOTNOTES

INDEX PART II. SEXUAL SELECTION—continued. CHAPTER XII. Secondary Sexual Characters of Fishes, Amphibians, and Reptiles. Fishes: Courtship and battles of the males—Larger size of the females—Males, bright colours and ornamental appendages; other strange characters—Colours and appendages acquired by the males during the breeding-season alone—Fishes with both sexes brilliantly coloured—Protective colours—The less conspicuous colours of the female cannot be accounted for on the principle of protection—Male fishes building nests, and taking charge of the ova and young. Amphibians: Differences in structure and colour between the sexes—Vocal organs. Reptiles: Chelonians—Crocodiles—Snakes, colours in some cases protective—Lizards, battles of—Ornamental appendages—Strange differences in structure between the sexes—Colours—Sexual differences almost as great as with birds 1-37 CHAPTER XIII. Secondary Sexual Characters of Birds. Sexual differences—Law of battle—Special weapons—Vocal organs—Instrumental music—Love-antics and dances—Decorations, permanent and seasonal—Double and single annual moults—Display of ornaments by the males 38-98 CHAPTER XIV. viBirds—continued Choice exerted by the female—Length of courtship—Unpaired birds—Mental qualities and taste for the beautiful—Preference or antipathy shewn by the female for particular males—Variability of birds—Variations sometimes abrupt—Laws of variation—Formation of ocelli—Gradations of character—Case of Peacock, Argus pheasant, and Urosticte 99-153 CHAPTER XV. Birds—continued. Discussion why the males alone of some species, and both sexes of other species, are brightly coloured—On sexually-limited inheritance, as applied to various structures and to brightly-coloured plumage—Nidification in relation to colour—Loss of nuptial plumage during the winter 154-182 CHAPTER XVI. Birds—continued. The immature plumage in relation to the character of the plumage in both sexes when adult—Six classes of cases—Sexual differences between the males of closely-allied or representative species—The female assuming the characters of the male—Plumage of the young in relation to the summer and winter plumage of the adults—On the increase of beauty in the Birds of the World—Protective colouring—Conspicuously-coloured birds—Novelty appreciated—Summary of the four chapters on birds 183-238 CHAPTER XVII. vii Secondary Sexual Characters of Mammals. The law of battle—Special weapons, confined to the males—Cause of absence of weapons in the female—Weapons common to both sexes, yet primarily acquired by the male—Other uses of such weapons—Their high importance—Greater size of the male—Means of defence—On the preference shewn by either sex in the pairing of quadrupeds 239-273 CHAPTER XVIII. Secondary Sexual Characters of Mammals.—continued. Voice—Remarkable sexual peculiarities in seals—Odour—Development of the hair—Colour of the hair and skin—Anomalous case of the female being more ornamented than the male—Colour and ornaments due to sexual selection—Colour acquired for the sake of protection—Colour, though common to both sexes, often due to sexual selection—On the disappearance of spots and stripes in adult quadrupeds—On the colours and ornaments of the Quadrumana—Summary 274-315 CHAPTER XIX. Secondary Sexual Characters of Mammals.—continued. Differences between man and woman—Causes of such differences and of certain characters common to both sexes—Law of battle—Differences in mental powers—and voice—On the influence of beauty in determining the marriages of mankind—Attention paid by savages to ornaments—Their ideas of beauty in woman—The tendency to exaggerate each natural peculiarity 316-354 CHAPTER XX. Secondary Sexual Characters of Man—continued. On the effects of the continued selection of women according to a different standard of beauty in each race—On the causes which interfere with sexual selection in civilised and savage nations—Conditions favourable to sexual selection during primeval times—On the manner of action of sexual selection with mankind—On the women in savage tribes having some power to choose their husbands—Absence of hair on the body, and development of the beard—Colour of the skin—Summary 355-384 CHAPTER XXI. General Summary and Conclusion. Main conclusion that man is descended from some lower form—Manner of development—Genealogy of man—Intellectual and moral faculties—Sexual selection—Concluding remarks 385-405 Index 406

THE DESCENT OF MAN AND SELECTION IN RELATION TO SEX By Charles Darwin

CONTENTS PREFACE TO THE SECOND EDITION. DETAILED TABLE OF CONTENTS INTRODUCTION. THE DESCENT OF MAN; AND SELECTION IN RELATION TO SEX. INTRODUCTION.