Origin of Species Variorum

Comparison with 1869

of different breeds of cattle in relation to an artificially imperfect state of the male sex; for oxen of certain breeds have longer horns than the oxen of other breeds, relatively to the length of the horns in both the bulls and cows of these same breeds. Hence I can see no great difficulty in any character becoming correlated with the sterile condition of certain members of insect-communities: the difficulty lies in understanding how such correlated modifications of structure could have been slowly accumulated by natural selection.

This difficulty, though appearing insuperable, is lessened, or, as I believe, disappears, when it is remembered that selection may be applied to the family, as well as to the individual, and may thus gain the desired end. ↑ Thus, a well-flavoured vegetable is cooked, and the individual is destroyed; but the horticulturist sows seeds of the same stock, and confidently expects to get nearly the same variety; breeders of cattle wish the flesh and fat to be well marbled together; the animal has been slaughtered, but the breeder goes with confidence to the same family. I have such faith in the powers of selection, that I do not doubt that a breed of cattle, always yielding oxen with extraordinarily long horns, could be slowly formed by carefully watching which individual bulls and cows, when matched, produced oxen with the longest horns; and yet no one ox could ever have propagated its kind. Here is a better and real illustration: according to M. Verlot, some varieties of the double annual stock of various colours, from having been long carefully selected to the right degree, always produce by seed a large proportion of plants bearing double and quite sterile flowers; so that, if the variety had not likewise yielded others, it would at once have become extinct; but it always yields some single and fertile plants, which differ from ordinary single varieties only in their power of producing the two forms. Thus the fertile plants producing single flowers may be compared with the males and females

of different breeds of cattle in relation to an artificially imperfect state of the male sex; for oxen of certain breeds have longer horns than in other breeds, in comparison with the horns of the bulls or cows of these same breeds. Hence I can see no real difficulty in any character having become correlated with the sterile condition of certain members of insect-communities: the difficulty lies in understanding how such correlated modifications of structure could have been slowly accumulated by natural selection.

This difficulty, though appearing insuperable, is lessened, or, as I believe, disappears, when it is remembered that selection may be applied to the family, as well as to the individual, and may thus gain the desired end. ↑ Thus, breeders of cattle wish the flesh and fat to be well marbled together; the animal has been slaughtered, but the breeder has gone with confidence to the same stock and has succeeded. .. Such faith may be placed in the power of selection, that probably a breed of cattle, always yielding oxen with extraordinarily long horns, could be slowly formed by carefully watching which individual bulls and cows, when matched, produced oxen with the longest horns; and yet no one ox would ever have propagated its kind. Here is a better and real illustration: according to M. Verlot, some varieties of the double annual stock of various colours, from having been long carefully selected to the right degree, always produce by seed a large proportion of plants bearing double and quite sterile flowers; so that, if the variety had not yielded others, it would at once have become extinct; but it likewise always yields some single and fertile plants, which differ only in their power of producing two forms, from ordinary single varieties. Thus these single and fertile plants may be compared with the males and females