Seite - 47 - in The Origin of Species
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SELECTION BY MAN 47
nary cases. If selection consisted merely in separating some
very distinct variety, and breeding from it. the principle would
be so obvious as hardly to be worth notice ; but its importance
consists in the great effect produced by the accumulation in
one direction, during successive generations, of differences
absolutely inappreciable by an uneducated eye—differences
which I for one have vainly attempted to appreciate. Not
one man in a thousand has accuracy of eye and judgment
sufficient to become an eminent breeder. If gifted with these
qualities, and he studies his subject for years, and devotes his
lifetime to it with indomitable perseverance, he will succeed,
and may make great improvements ; if he wants any of these
qualities, he will assuredly fail. Few would readily believe
in the natural capacity and years of practice requisite to be-
come even a skilful pigeon-fancier.
The same principles are followed by horticulturists; but
the variations are here often more abrupt. No one supposes
'that our choicest productions have been produced by a single
variation from the aboriginal stock. We have proofs that
this has not been so in several cases in which exact records
have been kept; thus, to give a very trifling instance, the
steadily increasing size of the common gooseberry may be
quoted. We see an astonishing improvement in many flor-
ists' flowers, when the flowers of the present day are com-
pared with drawings made only twenty or thirty years ago.
When a race of plants is once pretty well established, the
seed-raisers do not pick out the best plants, but merely go
.over their seed-beds, and pull up the "rogues," as they call
the plants that deviate from the proper standard. With ani-
mals this kind of selection is, in fact, likewise followed; for
hardly any one is so careless as to breed from his worst
animals.
In regard to plants, there is another means of observing
the accumulated effects of selection—namely, by comparing
the diversity of flowers in the different varieties of the same
species in the flower-garden ; the diversity of leaves, pods, or
tubers, or whatever part is valued, in the kitchen-garden, in
comparison with the flowers of the same varieties ; and the
diversity of fruit of the same species in the orchard, in com-
parison with the leaves and flowers of the same set of vari-
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Buch The Origin of Species"
The Origin of Species
- Titel
- The Origin of Species
- Autor
- Charles Darwin
- Verlag
- P. F. Collier & Son
- Ort
- New York
- Datum
- 1909
- Sprache
- englisch
- Lizenz
- PD
- Abmessungen
- 10.5 x 16.4 cm
- Seiten
- 568
- Schlagwörter
- Evolutionstheorie, Evolution, Theory of Evolution, Naturwissenschaft, Natural Sciences
- Kategorien
- International
- Naturwissenschaften Biologie
Inhaltsverzeichnis
- EDITOR'S INTRODUCTION 5
- AN HISTORICAL SKETCH of the Progress of Opinion on the Origin of Species 9
- INTRODUCTION 21
- Variation under Domestication 25
- Variation under Nature 58
- Struggle for Existence 76
- Natural Selection; or the Survival of the Fittest 93
- Laws of Variation 145
- Difficulties of the Theory 178
- Miscellaneous Objections to the Theory of Natural Selection 219
- Instinct 262
- Hybridism 298
- On the Imperfection of the Geological Record 333
- On the Geological Succession of Organic Beinss 364
- Geographical Distribution 395
- Geographical Distribution - continued 427
- Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs 450
- Recapitulation and Conclusion 499
- GLOSSARY 531
- INDEX 541