Persia, we can, I think, clearly trace the stages through which they
have insensibly passed, and come to differ so greatly from the
rock-pigeon.
Youatt gives an excellent illustration of the effects of a course of
selection, which may be considered as unconsciously followed, in so far
that the breeders could never have expected or even have wished to have
produced the result which ensued namely, the production of two distinct
strains. The two flocks of Leicester sheep kept by Mr. Buckley and Mr.
Burgess, as Mr. Youatt remarks, have been purely bred from the
original stock of Mr. Bakewell for upwards of fifty years. There is not
a suspicion existing in the mind of any one at all acquainted with the
subject that the owner of either of them has deviated in any one
instance from the pure blood of Mr. Bakewell s flock, and yet the
difference between the sheep possessed by these two gentlemen is so
great that they have the appearance of being quite different
varieties.
If there exist savages so barbarous as never to think of the inherited
character of the offspring of their domestic animals, yet any one
animal particularly useful to them, for any special purpose, would be
carefully preserved during famines and other accidents, to which
savages are so liable, and such choice animals would thus generally
leave more offspring than the inferior ones; so that in this case there
would be a kind of unconscious selection going on. We see the value set
on animals even by the barbarians of Tierra del Fuego, by their killing
and devouring their old women, in times of dearth, as of less value
than their dogs.
In plants the same gradual process of improvement, through the
occasional preservation of the best individuals, whether or not
sufficiently distinct to be ranked
at their first appearance as distinct varieties, and whether or not two
or more species or races have become blended together by crossing, may
plainly be recognised in the increased size and beauty which we now see
in the varieties of the heartsease, rose, pelargonium, dahlia, and
other plants, when compared with the older varieties or with their
parent-stocks. No one would ever expect to get a first-rate heartsease
or dahlia from the seed of a wild plant. No one would expect to raise a
first-rate melting pear from the seed of a wild pear, though he might
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