The Descent of Man

ed by a medical man, that some years ago during
each summer, but not during the winter,
his hands became marked with light brown
patches, like, although larger than freckles, and
that these patches were never affected by sunburning,
whilst the white parts of his skin have
on several occasions been much inflamed and
blistered. With the lower animals there is, also,
a constitutional difference in liability to the
action of the sun between those parts of the
skin clothed with white hair and other parts.
(64. 'Variation of Animals and Plants under
Domestication,' vol. ii. pp. 336, 337.) Whether
the saving of the skin from being thus burnt is
of sufficient importance to account for a dark
tint having been gradually acquired by man
through natural selection, I am unable to judge.
If it be so, we should have to assume that the
natives of tropical America have lived there for
a much shorter time than the Negroes in Africa,
or the Papuans in the southern parts of the Malay
archipelago, just as the lighter-coloured