Seite - 512 - in The Origin of Species
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Text der Seite - 512 -
512 ORIGIN OF SPECIES
absolutely perfect, as in the case even of the human eye; or
if some of them be abhorrent to our ideas of fitness. We
need not marvel at the sting of the bee, when used against
an enemy, causing the bee's own death
; at drones being
produced in such great numbers for one single act, and being
then slaughtered by their sterile sisters
; at the astonishing
waste of pollen by our fir-trees ; at the instinctive hatred o£
the queen-bee for her own fertile daughters; at ichneumon-
idae feeding within the living bodies of caterpillars; or at
other such cases. The wonder indeed is, on the theory of
natural selection^ that more cases of the want of absolute
perfection have not been detected.
The complex and little known laws governing the produc-
tion of varieties are the same, as far as we can judge, with
the laws which have governed the production of distinct
species. In both cases physical conditions seem to have pro-
duced some direct and definite effect, but how much we can-
not say. Thus, when varieties enter any new station, they
occasionally assume some of the characters proper to the
species of that station. With both varieties and species, use
and disuse seem to have produced a considerable effect; for
it is impossible to resist this conclusion when we look, for
instance, at the logger-headed duck, which has wings in-
capable of flight, in nearly the same condition as in the do-
mestic duck; or when we look at the burrowing tucu-tucu,
which is occasionally blind, and then at certain moles, which
are habitually blind and have their eyes covered with skin;
or when we look at the blind animals inhabiting the dark
caves of America and Europe. With varieties and species,
correlated variation seems to have played an important part,
so that when one part has been modified other parts have
been necessarily modified. With both varieties and species,
reversions to long-lost characters occasionally occur. How
inexplicable on the theory of creation is the occasional ap-
pearance of stripes on the shoulders and legs of the several
species of the horse-genus and of their hybrids ! How simply
is this fact explained if we believe that these species are all
descended from a striped progenitor, in the same manner as
the several domestic breeds of the pigeon are descended
from the blue and barred rock-pigeon !
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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