Seite - 235 - in The Origin of Species
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Text der Seite - 235 -
THEORY OF NATURAL SELECTION 235
solve the simpler problem why, of two races of savages, one
has risen higher in the scale of civilisation than the other;
and this apparently implies increased brain-power.
We will return to Mr. Mivart's other objections. Insects
often resemble for the sake of protection various objects, such
as green or decayed leaves, dead twigs, bits of lichen, flowers,
spines, excrement of birds, and living insects ; but to this lat-
ter point I shall hereafter recur. The resemblance is often
wonderfully close, and is not confined to colour, but extends
to form, and even to the manner in which the insects hold
themselves. The caterpillars which project motionless like
dead twigs from the bushes on which they feed, offer an ex-
cellent instance of a resemblance of this kind. The cases of
the imitation of such objects as the excrement of birds, are
rare and exceptional. On this head, Mr. Mivart remarks,
"As, according to Mr. Darwin's theory, there is a constant
tendency to indefinite variation, and as the minute incipient
variations will be in all directions, they must tend to neutral-
ise each other, and at first to form such unstable modifications
that it is difficult, if not impossible, to see how such indefinite
oscillations of infinitesimal beginnings can ever build up a
sufficiently appreciable resemblance to a leaf, bamboo, or other
object, for Natural Selection to seize upon and perpetuate."
But in all the foregoing cases the insects in their original
state no doubt presented some rude and accidental resem-
blance to an object commonly found in the stations frequented
by them. Nor is this at all improbable, considering the al-
most infinite number of surrounding objects and the diver-
sity in form and colour of the hosts of insects which exist.
As some rude resemblance is necessary for the first start, we
can understand how it is that the larger and higher animals
do not (with the exception, as far as I know, of one fish")
resemble for the sake of protection special objects, but only
the surface which commonly surrounds them, and this chiefly
in colour. Assuming that an insect originally happened to
resemble in some degree a dead twig or a decayed leaf, and
that it varied slightly in many ways, then all the variations
which rendered the insect at all more like any such object,
and thus favoured its escape, would be preserved, whilst other
variations would be neglected and ultimately lost; or, if they
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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