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The Descent of Man

The Descent of Man

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I conclude, therefore, that the habit <strong>of</strong> moulting<br />

twice in the year was in most or all cases first<br />

acquired for some distinct purpose, perhaps for<br />

gaining a warmer winter covering; and that<br />

variations in the plumage occurring during the<br />

summer were accumulated through sexual selection,<br />

and transmitted to the <strong>of</strong>fspring at the<br />

same season <strong>of</strong> the year; that such variations<br />

were inherited either by both sexes or by the<br />

males alone, according to the form <strong>of</strong> inheritance<br />

which prevailed. This appears more probable<br />

than that the species in all cases originally<br />

tended to retain their ornamental plumage during<br />

the winter, but were saved from this<br />

through natural selection, resulting from the<br />

inconvenience or danger thus caused.<br />

I have endeavoured in this chapter to shew that<br />

the arguments are not trustworthy in favour <strong>of</strong><br />

the view that weapons, bright colours, and various<br />

ornaments, are now confined to the males<br />

owing to the conversion, by natural selection,

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