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The Variation of Animals and Plants Under Domestication, Volumen2
Vista completa - 1890
The Variation of Animals and Plants Under Domestication, Volumen1
Vista completa - 1890
according affected animals appearance authority beak bearing become believe birds blue body bones branches breeds buds called Carriers cattle character closely colour common considered countries crossed cultivated descended described developed distinct dogs domestic domestic pigeons doubt duck ears elongated English existed extremely fact feathers feet female flowers four fowls fruit Gardener's give given head hybrids important inches increased India inherited instance Islands kinds known latter leaves legs length less male manner marked namely natural nearly observed occasionally origin parent peach period pigeons plants points present probably produced rabbits races raised remarkable resemble respect reversion rock-pigeon seed seedlings seen selection shape short single skin skull sometimes species specimens striped structure tail trees true Tumbler variable variation varieties various vary vertebræ weight whilst whole wild wings young
Página 6 - It has been said that I speak of natural selection as an active power or Deity; but who objects to an author speaking of the attraction of gravity as ruling the movements of the planets?
Página 4 - ... an uneducated eye, he has effected wonderful changes and improvements. It can, also, be clearly shown that man, without any intention or thought of improving the breed, by preserving in each successive generation the individuals which he prizes most, and by destroying the worthless individuals, slowly, though surely, induces great changes.
Página 26 - ... it is highly probable that the domestic dogs of the world are descended from two well-defined species of wolf (viz. C. lupus and C. latrans), and from two or three other doubtful species (namely, the European, Indian, and North African wolves) ; from at least one or two South American canine species ; from several races or species of jackal ; and perhaps from one or more extinct species.
Página 9 - In scientific investigations it is permitted to invent any hypothesis, and if it explains various large and independent classes of facts it rises to the rank of a well-grounded theory.
Página 7 - So again it is difficult to avoid personifying the word Nature ; but I mean by Nature, only the aggregate action and product of many natural laws, and by laws the sequence of events as ascertained by us.