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The Descent of Man

The Descent of Man

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are likewise marked and shaded, according to<br />

our standard <strong>of</strong> taste, with extreme elegance. In<br />

such cases we may conclude that both natural<br />

and sexual selection have acted conjointly for<br />

protection and ornament. Whether any bird<br />

exists which does not possess some special attraction,<br />

by which to charm the opposite sex,<br />

may be doubted. When both sexes are so obscurely<br />

coloured that it would be rash to assume<br />

the agency <strong>of</strong> sexual selection, and when no<br />

direct evidence can be advanced shewing that<br />

such colours serve as a protection, it is best to<br />

own complete ignorance <strong>of</strong> the cause, or, which<br />

comes to nearly the same thing, to attribute the<br />

result to the direct action <strong>of</strong> the conditions <strong>of</strong><br />

life.<br />

Both sexes <strong>of</strong> many birds are conspicuously,<br />

though not brilliantly coloured, such as the<br />

numerous black, white, or piebald species; and<br />

these colours are probably the result <strong>of</strong> sexual<br />

selection. With the common blackbird, caper-

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