Seite - 451 - in The Origin of Species
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Text der Seite - 451 -
CLASSIFICATION 451
tend to go on increasing in size. I further attempted to show
that from the varying descendants of each species trying to
occupy as many and as different places as possible in the
economy of nature, they constantly tend to diverge in char-
acter. This latter conclusion is supported by observing the
great diversity of forms which, in any small area, come into
the closest competition, and by certain facts in natural-
isation.
I attempted also to show that there is a steady tendency in
the forms which are increasing in number and diverging in
character, to supplant and exterminate the preceding, less
divergent and less improved forms. I request the reader to
turn to the diagram illustrating the action, as formerly ex-
plained, of these several principles; and he will see that the
inevitable result is, that the modified descendants proceeding
from one progenitor become broken up into groups subordi-
nate to groups. In the diagram each letter on the uppermost
line may represent a genus including several species ; and the
whole of the genera along this upper line form together one
class, for all are descended from one ancient parent, and,
consequently, have inherited something in common. But the
three genera on the left hand have, on this same principle,
much in common, and form a sub-family, distinct from that
containing the next two genera on the right hand, which
diverged from a common parent at the fifth stage of descent.
These five genera have also much in common, though less
than when grouped in sub-families ; and they form a family
distinct from that containing the three genera still farther to
the right hand, which diverged at an earlier period. And all
these genera, descended from (A), form an order distinct
from the genera descended from (I). So that we here have
many species descended from a single progenitor grouped
into genera; and the genera into sub-families, families, and
orders, all under one great class. The grand fact of the
natural subordination of organic beings in groups under
groups, which, from its familiarity, does not always suffi-
ciently strike us, is in my judgment thus explained. No
doubt organic beings, like all other objects, can be classed in
many ways, either artificially by single characters, or more
naturally by a number of characters. We know, for instance,
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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