An instance of unconscious selection leading to distinct
results in modern times is afforded by two flocks of Leicester sheep
which both originated from the same stock, and were then bred pure for
upwards of fifty years by two gentlemen, Mr. Buckley and Mr. Burgess.
Mr. Youatt, one of the greatest authorities on breeding domestic
animals, says: "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
original 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." In this case there was no desire to deviate
from the original breed, and the difference must have arisen from some
slight difference of taste or judgment in selecting, each year, the
parents for the next year's stock, combined perhaps with some direct
effect of the slight differences of climate and soil on the two farms.
Most of our domesticated animals and cultivated plants have come to us
from the earliest seats of civilisation in Western Asia or Egypt, and
have therefore been the subjects of human care and selection for some
thousands of years, the result being that, in many cases, we do not know
the wild stock from which they originally sprang.
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