Seite - 455 - in The Origin of Species
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Text der Seite - 455 -
CLASSIFICATION 455
been covered with feathers instead of hair, this external and
trifling character would have been considered by naturalists
as an important aid in determining the degree of affinity of
this strange creature to birds.
The importance, for classification, of trifling characters,
mainly depends on their being correlated with many other
characters of more or less importance. The value indeed of
an aggrjgate of characters is very evident in natural history.
Hence, as has often been remarked, a species may depart
from its allies in several characters, both of high physiologi-
cal importance, and of almost universal prevalence, and yet
leave us in no doubt where it should be ranked. Hence, also,
it has been found that a classification founded on any single
character, however important that may be, has always failed ;
for no part of the organisation is invariably constant. The
importance of an aggregate of characters, even when none
are important, alone explains the aphorism enunciated by
Linnaeus, namely, that the characters do not give the genus,
but the genus gives the characters ; for this seems founded
on the appreciation ofmany triflingpoints of resemblance, too
slight to be defined. Certain plants, belonging to the Mal-
pighiaceae, bear perfect and degraded flowers; in the latter,
as A. de Jussieu has remarked, "the greater number of the
characters proper to the species, to the genus, to the family,
to the class, disappear, and thus laugh at our classification."
When Aspicarpa produced in France, during several years,
only these degraded flowers, departing so wonderfully in a
number of the most important points of structure from the
proper type of the order, yet M. Richard sagaciously saw,
as Jussieu observes, that this genus should still be retained
amongst the Malpighiacese. This case well illustrates the
spirit of our classifications.
Practically, when naturalists are at work, they do not
trouble themselves about the physiological value of the char-
acters which they use in defining a group or in allocating any
particular species. If they find a character nearly uniform,
and common to a great number of forms, and not common
to others, they use it as one of high value; if common to
some lesser number, they use it as of subordinate value. This
principle has been broadly confessed by some naturalists to
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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