Some races are much more hairy than others, especially the males;
but it must not be assumed that the more hairy races, such as the
European, have retained their primordial condition more completely
than the naked races, such as the Kalmucks or Americans. It is more
probable that the hairiness of the former is due to partial reversion;
for characters which have been at some former period long inherited
are always apt to return. We have seen that idiots are often very
hairy, and they are apt to revert in other characters to a lower
animal type. It does not appear that a cold climate has been
influential in leading to this kind of reversion; excepting perhaps
with the negroes, who have been reared during several generations in
the United States,* and possibly with the Ainos, who inhabit the
northern islands of the Japan archipelago. But the laws of inheritance
are so complex that we can seldom understand their action. If the
greater hairiness of certain races be the result of reversion,
unchecked by any form of selection, its extreme variability, even
within the limits of the same race, ceases to be remarkable.*(2)
* Investigations into Military and Anthropological Statistics of
American Soldiers, by B. A. Gould, 1869, p. 568:- Observations were
carefully made on the hairiness of 2,129 black and coloured
soldiers, whilst they were bathing; and by looking to the published
table, "it is manifest at a glance that there is but little, if any,
difference between the white and the black races in this respect."
It is, however, certain that negroes in their native and much hotter
land of Africa, have remarkably smooth bodies. It should be
particularly observed, that both pure blacks and mulattoes were
included in the above enumeration; and this is an unfortunate
circumstance, as in accordance with a principle, the truth of which
I have elsewhere proved, crossed races of man would be eminently
liable to revert to the primordial hairy character of their early
ape-like progenitors.
*(2) Hardly any view advanced in this work has met with so much
disfavour (see for instance, Spengel, Die Fortschritte des
Darwinismus, 1874, p. 80) as the above explanation of the loss of hair
in mankind through sexual selection; but none of the opposed arguments
seem to me of much weight, in comparison with the facts shewing that
the nudity of the skin is to a certain extent a secondary sexual
character in man and in some of the Quadrumana.
With respect to the beard in man, if we turn to our best guide,
the Quadrumana, we find beards equally developed in both sexes of many
species, but in some, either confined to the males, or more
developed in them than in the females. From this fact and from the
curious arrangement, as well as the bright colours of the hair about
the heads of many monkeys, it is highly probable, as before explained,
that the males first acquired their beards through sexual selection as
an ornament, transmitting them in most cases, equally or nearly so, to
their offspring of both sexes. We know from Eschricht* that with
mankind the female as well as the male foetus is furnished with much
hair on the face, especially round the mouth; and this indicates
that we are descended from progenitors of whom both sexes were
bearded. It appears therefore at first sight probable that man has
retained his beard from a very early period, whilst woman lost her
beard at the same time that her body became almost completely divested
of hair. Even the colour of our beards seems to have been inherited
from an ape-like progenitor; for when there is any difference in
tint between the hair of the head and the beard, the latter is lighter
coloured in all monkeys and in man. In those Quadrumana in which the
male has a larger beard than that of the female, it is fully developed
only at maturity, just as with mankind; and it is possible that only
the later stages of development have been retained by man. In
opposition to this view of the retention of the beard from an early
period is the fact of its great variability in different races, and
even within the same race; for this indicates reversion,- long lost
characters being very apt to vary on re-appearance.
* "Uber die Richtung der Haare am Menschlichen Korper," in
Muller's Archiv. fur Anat. und Phys., 1837, s. 40.
Nor must we overlook the part which sexual selection may have played
in later times; for we know that with savages the men of the beardless
races take infinite pains in eradicating every hair from their faces
as something odious, whilst the men of the bearded races feel the
greatest pride in their beards. The women, no doubt, participate in
these feelings, and if so sexual selection can hardly have failed to
have effected something in the course of later times. It is also
possible that the long-continued habit of eradicating the hair may
have produced an inherited effect. Dr. Brown-Sequard has shewn that if
certain animals are operated on in a particular manner, their
offspring are affected. Further evidence could be given of the
inheritance of the effects of mutilations; but a fact lately
ascertained by Mr. Salvin* has a more direct bearing on the present
question; for he has shewn that the motmots, which are known
habitually to bite off the barbs of the two central tail-feathers,
have the barbs of these feathers naturally somewhat reduced.*(2)
Nevertheless, with mankind the habit of eradicating the beard and
the hairs on the body would probably not have arisen until these had
already become by some means reduced.
* On the tail-feathers of Motmots, Proceedings of the Zoological
Society, 1873, p. 429.
*(2) Mr. Sproat has suggested (Scenes and Studies of Savage Life,
1868, p. 25) this same view. Some distinguished ethnologists,
amongst others M. Gosse of Geneva, believe that artificial
modifications of the skull tend to be inherited.
It is difficult to form any judgment as to how the hair on the
head became developed to its present great length in many races.
Eschricht* states that in the human foetus the hair on the face during
the fifth month is longer than that on the head; and this indicates
that our semi-human progenitors were not furnished with long
tresses, which must therefore have been a late acquisition. This is
likewise indicated by the extraordinary difference in the length of
the hair in the different races; in the negro the hair forms a mere
curly mat; with us it is of great length, and with the American
natives it not rarely reaches to the ground. Some species of
Semnopithecus have their heads covered with moderately long hair,
and this probably serves as an ornament and was acquired through
sexual selection. The same view may perhaps be extended to mankind,
for we know that long tresses are now and were formerly much
admired, as may be observed in the works of almost every poet; St.
Paul says, "if a woman have long hair, it is a glory to her"; and we
have seen that in North America a chief was elected solely from the
length of his hair.
* Uber die Richtung, &c., s. 40.
Colour of the Skin.- The best kind of evidence that in man the
colour of the skin has been modified through sexual selection is
scanty; for in most races the sexes do not differ in this respect, and
only slightly, as we have seen, in others. We know, however, from
the many facts already given that the colour of the skin is regarded
by the men of all races as a highly important element in their beauty;
so that it is a character which would be likely to have been
modified through selection, as has occurred in innumerable instances
with the lower animals. It seems at first sight a monstrous
supposition that the jet-blackness of the negro should have been
gained through sexual selection; but this view is supported by various
analogies, and we know that negroes admire their own colour. With
mammals, when the sexes differ in colour, the male is often black or
much darker than the female; and it depends merely on the form of
inheritance whether this or any other tint is transmitted to both
sexes or to one alone. The resemblance to a negro in miniature of
Pithecia satanas with his jet black skin, white rolling eyeballs,
and hair parted on the top of the head, is almost ludicrous.
The colour of the face differs much more widely in the various kinds
of monkeys than it does in the races of man; and we have some reason
to believe that the red, blue, orange, almost white and black tints of
their skin, even when common to both sexes, as well as the bright
colours of their fur, and the ornamental tufts about the head, have
all been acquired through sexual selection. As the order of
development during growth, generally indicates the order in which
the characters of a species have been developed and modified during
previous generations; and as the newly-born infants of the various
races of man do not differ nearly as much in colour as do the
adults, although their bodies are as completely destitute of hair,
we have some slight evidence that the tints of the different races
were acquired at a period subsequent to the removal of the hair, which
must have occurred at a very early period in the history of man.
Summary.- We may conclude that the greater size, strength,
courage, pugnacity, and energy of man, in comparison with woman,
were acquired during primeval times, and have subsequently been
augmented, chiefly through the contests of rival males for the
possession of the females. The greater intellectual vigour and power
of invention in man is probably due to natural selection, combined
with the inherited effects of habit, for the most able men will have
succeeded best in defending and providing for themselves and for their
wives and offspring. As far as the extreme intricacy of the subject
permits us to judge, it appears that our male ape-like progenitors
acquired their beards as an ornament to charm or excite the opposite
sex, and transmitted them only to their male offspring. The females
apparently first had their bodies denuded of hair, also as a sexual
ornament; but they transmitted this character almost equally to both
sexes. It is not improbable that the females were modified in other
respects for the same purpose and by the same means; so that women
have acquired sweeter voices and become more beautiful than men.
It deserves attention that with mankind the conditions were in
many respects much more favourable for sexual selection during a
very early period, when man had only just attained to the rank of
manhood, than during later times. For he would then, as we may
safely conclude, have been guided more by his instinctive passions,
and less by foresight or reason. He would have jealously guarded his
wife or wives. He would not have practised infanticide; nor valued his
wives merely as useful slaves; nor have been betrothed to them
during infancy, Hence we may infer that the races of men were
differentiated, as far as sexual selection is concerned, in chief part
at a very remote epoch; and this conclusion throws light on the
remarkable fact that at the most ancient period, of which we have
not as yet any record, the races of man had already come to differ
nearly or quite as much as they do at the present day.
The views here advanced, on the part which sexual selection has
played in the history of man, want scientific precision. He who does
not admit this agency in the case of the lower animals, will disregard
all that I have written in the later chapters on man. We cannot
positively say that this character, but not that, has been thus
modified; it has however, been shewn that the races of man differ from
each other and from their nearest allies, in certain characters
which are of no service to them in their daily habits of life, and
which it is extremely probable would have been modified through sexual
selection. We have seen that with the lowest savages the people of
each tribe admire their own characteristic qualities,- the shape of
the head and face, the squareness of the cheek-bones, the prominence
or depression of the nose, the colour of the skin, the length of the
hair on the head, the absence of hair on the face and body, or the
presence of a great beard, and so forth. Hence these and other such
points could hardly fail to be slowly and gradually exaggerated,
from the more powerful and able men in each tribe, who would succeed
in rearing the largest number of offspring, having selected during
many generations for their wives the most strongly characterised and
therefore most attractive women. For my own part I conclude that of
all the causes which have led to the differences in external
appearance between the races of man, and to a certain extent between
man and the lower animals, sexual selection has been the most
efficient.
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