probably an injury to man, even in a hot climate, for he is thus
exposed to the scorching of the sun, and to sudden chills, especially
during wet weather. As Mr. Wallace remarks, the natives in all
countries are glad to protect their naked backs and shoulders with some
slight covering. No one supposes that the nakedness of the skin is any
direct advantage to man; his body therefore cannot have been divested
of hair through natural selection. (21. Contributions to the Theory of
Natural Selection, 1870, p. 346. Mr. Wallace believes (p. 350) that
some intelligent power has guided or determined the development of
man ; and he considers the hairless condition of the skin as coming
under this head. The Rev. T.R. Stebbing, in commenting on this view
( Transactions of Devonshire Association for Science, 1870) remarks,
that had Mr. Wallace employed his usual ingenuity on the question of
man s hairless skin, he might have seen the possibility of its
selection through its superior beauty or the health attaching to
superior cleanliness. ) Nor, as shewn in a former chapter, have we any
evidence that this can be due to the direct action of climate, or that
it is the result of correlated development.
The absence of hair on the body is to a certain extent a secondary
sexual character; for in all parts of the world women are less hairy
than men. Therefore we may reasonably suspect that this character has
been gained through sexual selection. We know that the faces of several
species of monkeys, and large surfaces at the posterior end of the body
of other species, have been denuded of hair; and this we may safely
attribute to sexual selection, for these surfaces are not only vividly
coloured, but sometimes, as with the male mandrill and female rhesus,
much more vividly in the one sex than in the other, especially during
the breeding-season. I am informed by Mr. Bartlett that, as these
animals gradually reach maturity, the naked surfaces grow larger
compared with the size of their bodies. The hair, however, appears to
have been removed, not for the sake of nudity, but that the colour of
the skin may be more fully displayed. So again with many birds, it
appears as if the head and neck had been divested of feathers through
sexual selection, to exhibit the brightly-coloured skin.
As the body in woman is less hairy than in man, and as this character
is common to all races, we may conclude that it was our female
semi-human ancestors who were first divested of hair, and that this
occurred at an extremely remote period before the several races had
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