rudest kind, and when his power of language was extremely imperfect,
would have deserved to be called man, must depend on the definition
which we employ. In a series of forms graduating insensibly from some
ape-like creature to man as he now exists, it would be impossible to
fix on any definite point when the term “man” ought to be used. But
this is a matter of very little importance. So, again, it is almost
a matter of indifference whether the so-called races of man are thus
designated, or are ranked as species or sub-species; but the latter
term appears the more appropriate. Finally, we may conclude that, when
the principle of evolution is generally accepted, as it surely will be
before long, the dispute between the monogenists and the polygenists
will die a silent and unobserved death.
THE THEORY OF A SINGLE PAIR.
One other question ought not to be passed over without notice, namely,
whether, as is sometimes assumed, each sub-species or race of man
has sprung from a single pair of progenitors. With our domestic
animals a new race can readily be formed by carefully matching the
varying offspring from a single pair, or even from a single individual
possessing some new character; but most of our races have been formed,
not intentionally from a selected pair, but unconsciously, by the
preservation of many individuals which have varied, however slightly,
in some useful or desired manner. If in one country stronger and
heavier horses, and in another country lighter and fleeter ones were
habitually preferred, we may feel sure that two distinct sub-breeds
would be produced in the course of time, without any one pair having
been separated and bred from in either country. Many races have been
thus formed, and their manner of formation is closely analogous to
that of natural species. We know, also, that the horses taken to the
Falkland Islands have, during successive generations, become smaller
and weaker, while those which have run wild on the Pampas have acquired
larger and coarser heads; and such changes are manifestly due, not to
any one pair, but to all the individuals having been subjected to the
same conditions, aided, perhaps, by the principle of reversion. The
new sub-breeds in such cases are not descended from any single pair,
but from many individuals which have varied in different degrees, but
in the same general manner; and we may conclude that the races of man
have been similarly produced, the modifications being either the direct
result of exposure to different conditions, or the indirect result of
some form of selection.
CIVILIZED OUT OF EXISTENCE.
[Descent of
Man, page 183.]
When Tasmania was first colonized the natives were roughly estimated
by some at seven thousand and by others at twenty thousand. Their
number was soon greatly reduced, chiefly by fighting with the English
and with each other. After the famous hunt by all the colonists, when
the remaining natives delivered themselves up to the government, they
consisted only of one hundred and twenty individuals, who were in 1832
transported to Flinders Island. This island, situated between Tasmania
and Australia, is forty miles long, and from twelve to eighteen
miles broad: it seems healthy, and the natives were well treated.
Nevertheless, they suffered greatly in health. In 1834 they consisted
(Bonwick, p. 250) of forty-seven adult males, forty-eight adult
females, and sixteen children, or in all of one hundred and eleven
souls. In 1835 only one hundred were left. As they continued rapidly to
decrease, and as they themselves thought that they should not perish
so quickly elsewhere, they were removed in 1847 to Oyster Cove in the
southern part of Tasmania. They then consisted (December 20, 1847) of
fourteen men, twenty-two women, and ten children. But the change of
site did no good. Disease and death still pursued them, and in 1864
one man (who died in 1869) and three elderly women alone survived.
The infertility of the women is even a more remarkable fact than the
liability of all to ill-health and death. At the time when only nine
women were left at Oyster Cove, they told Mr. Bonwick (p. 386), that
only two had ever borne children: and these two had together produced
only three children!
With respect to the cause of this extraordinary state of things,
Dr. Story remarks that death followed the attempts to civilize
the natives. “If left to themselves to roam as they were wont and
undisturbed, they would have reared more children, and there would have
been less mortality.” Another careful observer of the natives, Mr.
Davis, remarks: “The births have been few and the deaths numerous. This
may have been in a great measure owing to their change of living and
food; but more so to their banishment from the mainland of Van Diemen’s
Land, and consequent depression of spirits” (Bonwick, pp. 388, 390).
* * * * *
[Page 191.]
Although the gradual decrease and ultimate extinction of the races of
man is a highly complex problem, depending on many causes which differ
in different places and at different times, it is the same problem
as that presented by the extinction of one of the higher animals--of
the fossil horse, for instance, which disappeared from South America,
soon afterward to be replaced, within the same districts, by countless
troops of the Spanish horse. The New-Zealander seems conscious of this
parallelism, for he compares his future fate with that of the native
rat, now almost exterminated by the European rat. Though the difficulty
is great to our imagination, and really great, if we wish to ascertain
the precise causes and their manner of action, it ought not to be so to
our reason, as long as we keep steadily in mind that the increase of
each species and each race is constantly checked in various ways; so
that, if any new check, even a slight one, be superadded, the race will
surely decrease in number; and decreasing numbers will sooner or later
lead to extinction; the end, in most cases, being promptly determined
by the inroads of conquering tribes.
XI.
SEXUAL SELECTION AS AN AGENCY TO ACCOUNT FOR THE DIFFERENCES BETWEEN
THE RACES OF MAN.
[Descent of
Man, page 198.]
We have thus far been baffled in all our attempts to account for
the differences between the races of man; but there remains one
important agency, namely, sexual selection, which appears to have
acted powerfully on man, as on many other animals. I do not intend
to assert that sexual selection will account for all the differences
between the races. An unexplained residuum is left, about which we
can only say, in our ignorance, that as individuals are continually
born with, for instance, heads a little rounder or narrower, and with
noses a little longer or shorter, such slight differences might become
fixed and uniform, if the unknown agencies which induced them were to
act in a more constant manner, aided by long-continued intercrossing.
Such variations come under the provisional class, alluded to in our
second chapter, which for the want of a better term are often called
spontaneous. Nor do I pretend that the effects of sexual selection
can be indicated with scientific precision; but it can be shown that
it would be an inexplicable fact if man had not been modified by this
agency, which appears to have acted powerfully on innumerable animals.
It can further be shown that the differences between the races of
man, as in color, hairiness, form of features, etc., are of a kind
which might have been expected to come under the influence of sexual
selection.
STRUGGLE OF THE MALES FOR THE POSSESSION OF THE FEMALES.
[Descent of
Man, page 213.]
There can be no doubt that with almost all animals, in which the sexes
are separate, there is a constantly recurrent struggle between the
males for the possession of the females.
Our difficulty in regard to sexual selection lies in understanding how
it is that the males which conquer other males, or those which prove
the most attractive to the females, leave a greater number of offspring
to inherit their superiority than their beaten and less attractive
rivals. Unless this result does follow, the characters which give to
certain males an advantage over others could not be perfected and
augmented through sexual selection. When the sexes exist in exactly
equal numbers, the worst-endowed males will (except where polygamy
prevails) ultimately find females, and leave as many offspring, as well
fitted for their general habits of life, as the best-endowed males.
From various facts and considerations, I formerly inferred that with
most animals, in which secondary sexual characters are well developed,
the males considerably exceeded the females in number; but this is not
by any means always true. If the males were to the females as two to
one, or as three to two, or even in a somewhat lower ratio, the whole
affair would be simple; for the better-armed or more attractive males
would leave the largest number of offspring. But, after investigating,
as far as possible, the numerical proportion of the sexes, I do not
believe that any great inequality in number commonly exists. In most
cases sexual selection appears to have been effective in the following
manner:
Let us take any species, a bird for instance, and divide the females
inhabiting a district into two equal bodies, the one consisting of the
more vigorous and better-nourished individuals, and the other of the
less vigorous and healthy. The former, there can be little doubt, would
be ready to breed in the spring before the others; and this is the
opinion of Mr. Jenner Weir, who has carefully attended to the habits
of birds during many years. There can also be no doubt that the most
vigorous, best-nourished, and earliest breeders would on an average
succeed in rearing the largest number of fine offspring. The males,
as we have seen, are generally ready to breed before the females; the
strongest, and with some species the best armed of the males, drive
away the weaker; and the former would then unite with the more vigorous
and better-nourished females, because they are the first to breed. Such
vigorous pairs would surely rear a larger number of offspring than the
retarded females, which would be compelled to unite with the conquered
and less powerful males, supposing the sexes to be numerically equal;
and this is all that is wanted to add, in the course of successive
generations, to the size, strength, and courage of the males, or to
improve their weapons.
COURTSHIP AMONG THE LOWER ANIMALS.
[Page 214.]
But in very many cases the males which conquer their rivals do not
obtain possession of the females, independently of the choice of the
latter. The courtship of animals is by no means so simple and short
an affair as might be thought. The females are most excited by, or
prefer pairing with, the more ornamented males, or those which are the
best songsters, or play the best antics; but it is obviously probable
that they would at the same time prefer the more vigorous and lively
males, and this has in some cases been confirmed by actual observation.
Thus, the more vigorous females, which are the first to breed, will
have the choice of many males; and, though they may not always select
the strongest or best armed, they will select those which are vigorous
and well armed, and in other respects the most attractive. Both sexes,
therefore, of such early pairs would, as above explained, have an
advantage over others in rearing offspring; and this apparently has
sufficed, during a long course of generations, to add not only to
the strength and fighting powers of the males, but likewise to their
various ornaments or other attractions.
In the converse and much rarer case, of the males selecting particular
females, it is plain that those which were the most vigorous, and
had conquered others, would have the freest choice; and it is almost
certain that they would select vigorous as well as attractive females.
Such pairs would have an advantage in rearing offspring, more
especially if the male had the power to defend the female during the
pairing-season, as occurs with some of the higher animals, or aided her
in providing for the young. The same principles would apply if each
sex preferred and selected certain individuals of the opposite sex;
supposing that they selected not only the more attractive but likewise
the more vigorous individuals.
WHY THE MALE PLAYS THE MORE ACTIVE PART IN COURTING.
[Page 222.]
We are naturally led to inquire why the male, in so many and such
distinct classes, has become more eager than the female, so that he
searches for her, and plays the more active part in courtship. It would
be no advantage, and some loss of power, if each sex searched for
the other; but why should the male almost always be the seeker? The
ovules of plants after fertilization have to be nourished for a time;
hence the pollen is necessarily brought to the female organs--being
placed on the stigma by means of insects or the wind, or by the
spontaneous movements of the stamens; and, in the _Algæ_, etc., by the
locomotive power of the antherozoöids. With lowly-organized aquatic
animals, permanently affixed to the same spot, and having their sexes
separate, the male element is invariably brought to the female; and
of this we can see the reason, for even if the ova were detached
before fertilization, and did not require subsequent nourishment or
protection, there would yet be greater difficulty in transporting them
than the male element, because, being larger than the latter, they are
produced in far smaller numbers. So that many of the lower animals
are, in this respect, analogous with plants. The males of affixed and
aquatic animals, having been led to emit their fertilizing element in
this way, it is natural that any of their descendants, which rose in
the scale and became locomotive, should retain the same habit; and they
would approach the female as closely as possible, in order not to risk
the loss of the fertilizing element in a long passage of it through
the water. With some few of the lower animals, the females alone are
fixed, and the males of these must be the seekers. But it is difficult
to understand why the males of species, of which the progenitors
were primordially free, should invariably have acquired the habit of
approaching the females, instead of being approached by them. But, in
all cases, in order that the males should seek efficiently, it would
be necessary that they should be endowed with strong passions; and the
acquirement of such passions would naturally follow from the more eager
leaving a larger number of offspring than the less eager.
TRANSMISSION OF SEXUAL CHARACTERISTICS.
[Page 232.]
Why certain characters should be inherited by both sexes, and other
characters by one sex alone, namely, by that sex in which the character
first appeared, is in most cases quite unknown. We can not even
conjecture why, with certain sub-breeds of the pigeon, black striæ,
though transmitted through the female, should be developed in the
male alone, while every other character is equally transferred to
both sexes. Why, again, with cats, the tortoise-shell color should,
with rare exceptions, be developed in the female alone. The very same
character, such as deficient or supernumerary digits, color-blindness,
etc., may with mankind be inherited by the males alone of one family,
and in another family by the females alone, though in both cases
transmitted through the opposite as well as through the same sex.
Although we are thus ignorant, the two following rules seem often
to hold good: that variations which first appear in either sex at a
late period of life tend to be developed in the same sex alone; while
variations which first appear early in life in either sex tend to be
developed in both sexes. I am, however, far from supposing that this is
the sole determining cause.
* * * * *
[Page 233.]
An excellent case for investigation is afforded by the deer family.
In all the species, but one, the horns are developed only in the
males, though certainly transmitted through the females, and capable
of abnormal development in them. In the reindeer, on the other hand,
the female is provided with horns; so that, in this species, the horns
ought, according to our rule, to appear early in life, long before the
two sexes are mature, and have come to differ much in constitution.
In all the other species the horns ought to appear later in life,
which would lead to their development in that sex alone in which they
first appeared in the progenitor of the whole family. Now, in seven
species, belonging to distinct sections of the family, and inhabiting
different regions, in which the stags alone bear horns, I find that
the horns first appear at periods varying from nine months after birth
in the roebuck, to ten, twelve, or even more months in the stags of
the six other and larger species. But with the reindeer the case is
widely different; for, as I hear from Professor Nilsson, who kindly
made special inquiries for me in Lapland, the horns appear in the young
animals within four or five weeks after birth, and at the same time
in both sexes. So that here we have a structure developed at a most
unusually early age in one species of the family, and likewise common
to both sexes in this one species alone.
* * * * *
[Page 239.]
Finally, from what we have now seen of the relation which exists
in many natural species and domesticated races, between the period
of the development of their characters and the manner of their
transmission--for example, the striking fact of the early growth of the
horns in the reindeer, in which both sexes bear horns, in comparison
with their much later growth in the other species in which the male
alone bears horns--we may conclude that one, though not the sole
cause of characters being exclusively inherited by one sex, is their
development at a late age. And, secondly, that one, though apparently
a less efficient cause of characters being inherited by both sexes, is
their development at an early age, while the sexes differ but little
in constitution. It appears, however, that some difference must exist
between the sexes even during a very early embryonic period, for
characters developed at this age not rarely become attached to one sex.
AN OBJECTION ANSWERED.
[Descent of
Man, page 495.]
Several writers have objected to the whole theory of sexual selection,
by assuming that with animals and savages the taste of the female for
certain colors or other ornaments would not remain constant for many
generations; that first one color and then another would be admired,
and consequently that no permanent effect could be produced. We may
admit that taste is fluctuating, but it is not quite arbitrary. It
depends much on habit, as we see in mankind; and we may infer that
this would hold good with birds and other animals. Even in our own
dress, the general character lasts long, and the changes are to a
certain extent graduated. Abundant evidence will be given in two
places in a future chapter, that savages of many races have admired
for many generations the same cicatrices on the skin, the same
hideously perforated lips, nostrils, or ears, distorted heads, etc.;
and these deformities present some analogy to the natural ornaments
of various animals. Nevertheless, with savages such fashions do not
endure forever, as we may infer from the differences in this respect
between allied tribes on the same continent. So again the raisers of
fancy animals certainly have admired for many generations and still
admire the same breeds; they earnestly desire slight changes, which are
considered as improvements, but any great or sudden change is looked
at as the greatest blemish. With birds in a state of nature we have
no reason to suppose that they would admire an entirely new style of
coloration, even if great and sudden variation often occurred, which is
far from being the case. We know that dovecot pigeons do not willingly
associate with the variously colored fancy breeds; that albino birds do
not commonly get partners in marriage; and that the black ravens of the
Feroe Islands chase away their piebald brethren. But this dislike of
a sudden change would not preclude their appreciating slight changes,
any more than it does in the case of man. Hence with respect to taste,
which depends on many elements, but partly on habit and partly on a
love of novelty, there seems no improbability in animals admiring for
a very long period the same general style of ornamentation or other
attractions, and yet appreciating slight changes in colors, form, or
sound.
DIFFERENCE BETWEEN THE SEXES CREATED BY SEXUAL SELECTION.
[Page 563.]
There can be little doubt that the greater size and strength of man,
in comparison with woman, together with his broader shoulders, more
developed muscles, rugged outline of body, his greater courage and
pugnacity, are all due in chief part to inheritance from his half-human
male ancestors. These characters would, however, have been preserved or
even augmented during the long ages of man’s savagery, by the success
of the strongest and boldest men, both in the general struggle for life
and in their contest for wives; a success which would have insured
their leaving a more numerous progeny than their less favored brethren.
It is not probable that the greater strength of man was primarily
acquired through the inherited effects of his having worked harder than
woman for his own subsistence and that of his family; for the women in
all barbarous nations are compelled to work at least as hard as the
men. With civilized people the arbitrament of battle for the possession
of the women has long ceased; on the other hand, the men, as a general
rule, have to work harder than the women for their joint subsistence,
and thus their greater strength will have been kept up.
* * * * *
With respect to differences of this nature between man and woman, it
is probable that sexual selection has played a highly important part.
I am aware that some writers doubt whether there is any such inherent
difference; but this is at least probable from the analogy of the
lower animals which present other secondary sexual characters. No
one disputes that the bull differs in disposition from the cow, the
wild-boar from the sow, the stallion from the mare, and, as is well
known to the keepers of menageries, the males of the larger apes from
the females. Woman seems to differ from man in mental disposition,
chiefly in her greater tenderness and less selfishness; and this holds
good even with savages, as shown by a well-known passage in Mungo
Park’s “Travels,” and by statements made by many other travelers.
Woman, owing to her maternal instincts, displays these qualities toward
her infants in an eminent degree; therefore it is likely that she
would often extend them toward her fellow-creatures. Man is the rival
of other men; he delights in competition, and this leads to ambition
which passes too easily into selfishness. These latter qualities seem
to be his natural and unfortunate birthright. It is generally admitted
that with woman the powers of intuition, of rapid perception, and
perhaps of imitation, are more strongly marked than in man; but some,
at least, of these faculties are characteristic of the lower races, and
therefore of a past and lower state of civilization.
The chief distinction in the intellectual powers of the two sexes is
shown by man’s attaining to a higher eminence, in whatever he takes up,
than can woman--whether requiring deep thought, reason, or imagination,
or merely the use of the senses and hands. If two lists were made of
the most eminent men and women in poetry, painting, sculpture, music
(inclusive both of composition and performance), history, science,
and philosophy, with half a dozen names under each subject, the two
lists would not bear comparison. We may also infer, from the law of
the deviation from averages, so well illustrated by Mr. Galton, in
his work on “Hereditary Genius,” that if men are capable of a decided
pre-eminence over women in many subjects, the average of mental power
in man must be above that of woman.