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A BRIEF summary will be sufficient
to recall to the reader's mind
the more salient points in this
work. Many of the views which
have been advanced are highly
speculative, and some no doubt
will prove erroneous; but I have
in every case given the reasons
which have led me to one view
rather than to another. It seemed
worth while to try how far the
principle of evolution would
throw light on some of the more
complex problems in the natural
history of man. False facts are
highly injurious to the progress
of science, for they often endure
long; but false views, if supported
by some evidence, do little harm,
for every one takes a salutary
pleasure in proving their falseness:
and when this is done, one path
towards error is closed and the
road to truth is often at the
same time opened.
The main conclusion here arrived
at, and now held by many naturalists
who are well competent to form
a sound judgment is that man
is descended from some less highly
organised form. The grounds upon
which this conclusion rests will
never be shaken, for the close
similarity between man and the
lower animals in embryonic development,
as well as in innumerable points
of structure and constitution,
both of high and of the most
trifling importance,- the rudiments
which he retains, and the abnormal
reversions to which he is occasionally
liable,- are facts which cannot
be disputed. They have long been
known, but until recently they
told us nothing with respect
to the origin of man. Now when
viewed by the light of our knowledge
of the whole organic world, their
meaning is unmistakable. The
great principle of evolution
stands up clear and firm, when
these groups or facts are considered
in connection with others, such
as the mutual affinities of the
members of the same group, their
geographical distribution in
past and present times, and their
geological succession. It is
incredible that all these facts
should speak falsely. He who
is not content to look, like
a savage, at the phenomena of
nature as disconnected, cannot
any longer believe that man is
the work of a separate act of
creation. He will be forced to
admit that the close resemblance
of the embryo of man to that,
for instance, of a dog- the construction
of his skull, limbs and whole
frame on the same plan with that
of other mammals, independently
of the uses to which the parts
may be put- the occasional re-appearance
of various structures, for instance
of several muscles, which man
does not normally possess, but
which are common to the Quadrumana-
and a crowd of analogous facts-
all point in the plainest manner
to the conclusion that man is
the co-descendant with other
mammals of a common progenitor.
We have seen that man incessantly
presents individual differences
in all parts of his body and
in his mental faculties. These
differences or variations seem
to be induced by the same general
causes, and to obey the same
laws as with the lower animals.
In both cases similar laws of
inheritance prevail. Man tends
to increase at a greater rate
than his means of subsistence;
consequently he is occasionally
subjected to a severe struggle
for existence, and natural selection
will have effected whatever lies
within its scope. A succession
of strongly-marked variations
of a similar nature is by no
means requisite; slight fluctuating
differences in the individual
suffice for the work of natural
selection; not that we have any
reason to suppose that in the
same species, all parts of the
organisation tend to vary to
the same degree. We may feel
assured that the inherited effects
of the long-continued use or
disuse of parts will have done
much in the same direction with
natural selection. Modifications
formerly of importance, though
no longer of any special use,
are long-inherited. When one
part is modified, other parts
change through the principle
of correlation, of which we have
instances in many curious cases
of correlated monstrosities.
Something may be attributed to
the direct and definite action
of the surrounding conditions
of life, such as abundant food,
heat or moisture; and lastly,
many characters of slight physiological
importance, some indeed of considerable
importance, have been gained
through sexual selection.
No doubt man, as well as every
other animal, presents structures,
which seem to our limited knowledge,
not to be now of any service
to him, nor to have been so formerly,
either for the general conditions
of life, or in the relations
of one sex to the other. Such
structures cannot be accounted
for by any form of selection,
or by the inherited effects of
the use and disuse of parts.
We know, however, that many strange
and strongly-marked peculiarities
of structure occasionally appear
in our domesticated productions,
and if their unknown causes were
to act more uniformly, they would
probably become common to all
the individuals of the species.
We may hope hereafter to understand
something about the causes of
such occasional modifications,
especially through the study
of monstrosities: hence the labours
of experimentalists such as those
of M. Camille Dareste, are full
of promise for the future. In
general we can only say that
the cause of each slight variation
and of each monstrosity lies
much more in the constitution
of the organism, than in the
nature of the surrounding conditions;
though new and changed conditions
certainly play an important part
in exciting organic changes of
many kinds.
Through the means just specified,
aided perhaps by others as yet
undiscovered, man has been raised
to his present state. But since
he attained to the rank of manhood,
he has diverged into distinct
races, or as they may be more
fitly called, sub-species. Some
of these, such as the Negro and
European, are so distinct that,
if specimens had been brought
to a naturalist without any further
information, they would undoubtedly
have been considered by him as
good and true species. Nevertheless
all the races agree in so many
unimportant details of structure
and in so many mental peculiarities
that these can be accounted for
only by inheritance from a common
progenitor; and a progenitor
thus characterised would probably
deserve to rank as man.
It must not be supposed that
the divergence of each race from
the other races, and of all from
a common stock, can be traced
back to any one pair of progenitors.
On the contrary, at every stage
in the process of modification,
all the individuals which were
in any way better fitted for
their conditions of life, though
in different degrees, would have
survived in greater numbers than
the less well-fitted. The process
would have been like that followed
by man, when he does not intentionally
select particular individuals,
but breeds from all the superior
individuals, and neglects the
inferior. He thus slowly but
surely modifies his stock, and
unconsciously forms a new strain.
So with respect to modifications
acquired independently of selection,
and due to variations arising
from the nature of the organism
and the action of the surrounding
conditions, or from changed habits
of life, no single pair will
have been modified much more
than the other pairs inhabiting
the same country, for all will
have been continually blended
through free intercrossing.
By considering the embryological
structure of man,- the homologies
which he presents with the lower
animals,- the rudiments which
he retains,- and the reversions
to which he is liable, we can
partly recall in imagination
the former condition of our early
progenitors; and can approximately
place them in their proper place
in the zoological series. We
thus learn that man is descended
from a hairy, tailed quadruped,
probably arboreal in its habits,
and an inhabitant of the Old
World. This creature, if its
whole structure had been examined
by a naturalist, would have been
classed amongst the Quadrumana,
as surely as the still more ancient
progenitor of the Old and New
World monkeys. The Quadrumana
and all the higher mammals are
probably derived from an ancient
marsupial animal, and this through
a long series of diversified
forms, from some amphibian-like
creature, and this again from
some fish-like animal. In the
dim obscurity of the past we
can see that the early progenitor
of all the Vertebrata must have
been an aquatic animal provided
with branchiae, with the two
sexes united in the same individual,
and with the most important organs
of the body (such as the brain
and heart) imperfectly or not
at all developed. This animal
seems to have been more like
the larvae of the existing marine
ascidians than any other known
form.
The high standard
of our intellectual powers
and moral disposition
is the greatest difficulty which
presents itself, after we have
been driven to this conclusion
on the origin of man. But every
one who admits the principle
of evolution, must see that the
mental powers of the higher animals,
which are the same in kind with
those of man, though so different
in degree, are capable of advancement.
Thus the interval between the
mental powers of one of the higher
apes and of a fish, or between
those of an ant and scale-insect,
is immense; yet their development
does not offer any special difficulty;
for with our domesticated animals,
the mental faculties are certainly
variable, and the variations
are inherited. No one doubts
that they are of the utmost importance
to animals in a state of nature.
Therefore the conditions are
favourable for their development
through natural selection. The
same conclusion may be extended
to man; the intellect must have
been all-important to him, even
at a very remote period, as enabling
him to invent and use language,
to make weapons, tools, traps, &c.,
whereby with the aid of his social
habits, he long ago became the
most dominant of all living creatures.
A great stride
in the development of the intellect
will have followed,
as soon as the half-art and half-instinct
of language came into use; for
the continued use of language
will have reacted on the brain
and produced an inherited effect;
and this again will have reacted
on the improvement of language.
As Mr. Chauncey Wright* has well
remarked, the largeness of the
brain in man relatively to his
body, compared with the lower
animals, may be attributed in
chief part to the early use of
some simple form of language,-
that wonderful engine which affixes
signs to all sorts of objects
and qualities, and excites trains
of thought which would never
arise from the mere impression
of the senses, or if they did
arise could not be followed out.
The higher intellectual powers
of man, such as those of ratiocination,
abstraction, self-consciousness, &c.,
probably follow from the continued
improvement and exercise of the
other mental faculties.
* "On the Limits of Natural
Selection," in the North American
Review, Oct., 1870, p. 295.
The development of the moral
qualities is a more interesting
problem. The foundation lies
in the social instincts, including
under this term the family ties.
These instincts are highly complex,
and in the case of the lower
animals give special tendencies
towards certain definite actions;
but the more important elements
are love, and the distinct emotion
of sympathy. Animals endowed
with the social instincts take
pleasure in one another's company,
warn one another of danger, defend
and aid one another in many ways.
These instincts do not extend
to all the individuals of the
species, but only to those of
the same community. As they are
highly beneficial to the species,
they have in all probability
been acquired through natural
selection.
A moral being is one who is
capable of reflecting on his
past actions and their motives-
of approving of some and disapproving
of others; and the fact that
man is the one being who certainly
deserves this designation, is
the greatest of all distinctions
between him and the lower animals.
But in the fourth chapter I have
endeavoured to shew that the
moral sense follows, firstly,
from the enduring and ever-present
nature of the social instincts;
secondly, from man's appreciation
of the approbation and disapprobation
of his fellows; and thirdly,
from the high activity of his
mental faculties, with past impressions
extremely vivid; and in these
latter respects he differs from
the lower animals. Owing to this
condition of mind, man cannot
avoid looking both backwards
and forwards, and comparing past
impressions. Hence after some
temporary desire or passion has
mastered his social instincts,
he reflects and compares the
now weakened impression of such
past impulses with the ever-present
social instincts; and he then
feels that sense of dissatisfaction
which all unsatisfied instincts
leave behind them, he therefore
resolves to act differently for
the future,- and this is conscience.
Any instinct, permanently stronger
or more enduring than another,
gives rise to a feeling which
we express by saying that it
ought to be obeyed. A pointer
dog, if able to reflect on his
past conduct, would say to himself,
I ought (as indeed we say of
him) to have pointed at that
hare and not have yielded to
the passing temptation of hunting
it.
Social animals are impelled
partly by a wish to aid the members
of their community in a general
manner, but more commonly to
perform certain definite actions.
Man is impelled by the same general
wish to aid his fellows; but
has few or no special instincts.
He differs also from the lower
animals in the power of expressing
his desires by words, which thus
become a guide to the aid required
and bestowed. The motive to give
aid is likewise much modified
in man: it no longer consists
solely of a blind instinctive
impulse, but is much influenced
by the praise or blame of his
fellows. The appreciation and
the bestowal of praise and blame
both rest on sympathy; and this
emotion, as we have seen, is
one of the most important elements
of the social instincts. Sympathy,
though gained as an instinct,
is also much strengthened by
exercise or habit. As all men
desire their own happiness, praise
or blame is bestowed on actions
and motives, according as they
lead to this end; and as happiness
is an essential part of the general
good, the greatest-happinesss
principle indirectly serves as
a nearly safe standard of right
and wrong. As the reasoning powers
advance and experience is gained,
the remoter effects of certain
lines of conduct on the character
of the individual, and on the
general good, are perceived;
and then the self-regarding virtues
come within the scope of public
opinion, and receive praise,
and their opposites blame. But
with the less civilised nations
reason often errs, and many bad
customs and base superstitions
come within the same scope, and
are then esteemed as high virtues,
and their breach as heavy crimes.
The moral faculties are generally
and justly esteemed as of higher
value than the intellectual powers.
But we should bear in mind that
the activity of the mind in vividly
recalling past impressions is
one of the fundamental though
secondary bases of conscience.
This affords the strongest argument
for educating and stimulating
in all possible ways the intellectual
faculties of every human being.
No doubt a man with a torpid
mind, if his social affections
and sympathies are well developed,
will be led to good actions,
and may have a fairly sensitive
conscience. But whatever renders
the imagination more vivid and
strengthens the habit of recalling
and comparing past impressions,
will make the conscience more
sensitive, and may even somewhat
compensate for weak social affections
and sympathies.
The moral nature of man has
reached its present standard,
partly through the advancement
of his reasoning powers and consequently
of a just public opinion, but
especially from his sympathies
having been rendered more tender
and widely diffused through the
effects of habit, example, instruction,
and reflection. It is not improbable
that after long practice virtuous
tendencies may be inherited.
With the more civilised races,
the conviction of the existence
of an all-seeing Deity has had
a potent influence on the advance
of morality. Ultimately man does
not accept the praise or blame
of his fellows as his sole guide,
though few escape this influence,
but his habitual convictions,
controlled by reason, afford
him the safest rule. His conscience
then becomes the supreme judge
and monitor. Nevertheless the
first foundation or origin of
the moral sense lies in the social
instincts, including sympathy;
and these instincts no doubt
were primarily gained, as in
the case of the lower animals,
through natural selection.
The belief in God has often
been advanced as not only the
greatest, but the most complete
of all the distinctions between
man and the lower animals. It
is however impossible, as we
have seen, to maintain that this
belief is innate or instinctive
in man. On the other hand a belief
in all-pervading spiritual agencies
seems to be universal; and apparently
follows from a considerable advance
in man's reason, and from a still
greater advance in his faculties
of imagination, curiosity and
wonder. I am aware that the assumed
instinctive belief in God has
been used by many persons as
an argument for His existence.
But this is a rash argument,
as we should thus be compelled
to believe in the existence of
many cruel and malignant spirits,
only a little more powerful than
man; for the belief in them is
far more general than in a beneficent
Deity. The idea of a universal
and beneficent Creator does not
seem to arise in the mind of
man, until he has been elevated
by long-continued culture.
He who believes in the advancement
of man from some low organised
form, will naturally ask how
does this bear on the belief
in the immortality of the soul.
The barbarous races of man, as
Sir J. Lubbock has shewn, possess
no clear belief of this kind;
but arguments derived from the
primeval beliefs of savages are,
as we have just seen, of little
or no avail. Few persons feel
any anxiety from the impossibility
of determining at what precise
period in the development of
the individual, from the first
trace of a minute germinal vesicle,
man becomes an immortal being;
and there is no greater cause
for anxiety because the period
cannot possibly be determined
in the gradually ascending organic
scale.*
* The Rev. J. A. Picton gives
a discussion to this effect in
his New Theories and the Old
Faith, 1870.
I am aware that the conclusions
arrived at in this work will
be denounced by some as highly
irreligious; but he who denounces
them is bound to shew why it
is more irreligious to explain
the origin of man as a distinct
species by descent from some
lower form, through the laws
of variation and natural selection,
than to explain the birth of
the individual through the laws
of ordinary reproduction. The
birth both of the species and
of the individual are equally
parts of that grand sequence
of events, which our minds refuse
to accept as the result of blind
chance. The understanding revolts
at such a conclusion, whether
or not we are able to believe
that every slight variation of
structure,- the union of each
pair in marriage, the dissemination
of each seed,- and other such
events, have all been ordained
for some special purpose.
Sexual selection has been treated
at great length in this work;
for, as I have attempted to shew,
it has played an important part
in the history of the organic
world. I am aware that much remains
doubtful, but I have endeavoured
to give a fair view of the whole
case. In the lower divisions
of the animal kingdom, sexual
selection seems to have done
nothing: such animals are often
affixed for life to the same
spot, or have the sexes combined
in the same individual, or what
is still more important, their
perceptive and intellectual faculties
are not sufficiently advanced
to allow of the feelings of love
and jealousy, or of the exertion
of choice. When, however, we
come to the Arthropoda and Vertebrata,
even to the lowest classes in
these two great sub-kingdoms,
sexual selection has effected
much.
In the several great classes
of the animal kingdom,- in mammals,
birds, reptiles, fishes, insects,
and even crustaceans,- the differences
between the sexes follow nearly
the same rules. The males are
almost always the wooers; and
they alone are armed with special
weapons for fighting with their
rivals. They are generally stronger
and larger than the females,
and are endowed with the requisite
qualities of courage and pugnacity.
They are provided, either exclusively
or in a much higher degree than
the females, with organs for
vocal or instrumental music,
and with odoriferous glands.
They are ornamental with infinitely
diversified appendages, and with
the most brilliant or conspicuous
colours, often arranged in elegant
patterns, whilst the females
are unadorned. When the sexes
differ in more important structures,
it is the male which is provided
with special sense-organs for
discovering the female, with
locomotive organs for reaching
her, and often with prehensile
organs for holding her. These
various structures for charming
or securing the female are often
developed in the male during
only part of the year, namely
the breeding-season. They have
in many cases been more or less
transferred to the females; and
in the latter case they often
appear in her as mere rudiments.
They are lost or never gained
by the males after emasculation.
Generally they are not developed
in the male during early youth,
but appear a short time before
the age for reproduction. Hence
in most cases the young of both
sexes resemble each other; and
the female somewhat resembles
her young offspring throughout
life. In almost every great class
a few anomalous cases occur,
where there has been an almost
complete transposition of the
characters proper to the two
sexes; the females assuming characters
which properly belong to the
males. This surprising uniformity
in the laws regulating the differences
between the sexes in so many
and such widely separated classes,
is intelligible if we admit the
action of one common cause, namely
sexual selection.
Sexual selection depends on
the success of certain individuals
over others of the same sex,
in relation to the propagation
of the species; whilst natural
selection depends on the success
of both sexes, at all ages, in
relation to the general conditions
of life. The sexual struggle
is of two kinds; in the one it
is between individuals of the
same sex, generally the males,
in order to drive away or kill
their rivals, the females remaining
passive; whilst in the other,
the struggle is likewise between
the individuals of the same sex,
in order to excite or charm those
of the opposite sex, generally
the females, which no longer
remain passive, but select the
more agreeable partners. This
latter kind of selection is closely
analogous to that which man unintentionally,
yet effectually, brings to bear
on his domesticated productions,
when he preserves during a long
period the most pleasing or useful
individuals, without any wish
to modify the breed.
The laws of inheritance determine
whether characters gained through
sexual selection by either sex
shall be transmitted to the same
sex, or to both; as well as the
age at which they shall be developed.
It appears that variations arising
late in life are commonly transmitted
to one and the same sex. Variability
is the necessary basis for the
action of selection, and is wholly
independent of it. It follows
from this, that variations of
the same general nature have
often been taken advantage of
and accumulated through sexual
selection in relation to the
propagation of the species, as
well as through natural selection
in relation to the general purposes
of life. Hence secondary sexual
characters, when equally transmitted
to both sexes can be distinguished
from ordinary specific characters
only by the light of analogy.
The modifications acquired through
sexual selection are often so
strongly pronounced that the
two sexes have frequently been
ranked as distinct species, or
even as distinct genera. Such
strongly-marked differences must
be in some manner highly important;
and we know that they have been
acquired in some instances at
the cost not only of inconvenience,
but of exposure to actual danger.
The belief in the power of sexual
selection rests chiefly on the
following considerations. Certain
characters are confined to one
sex; and this alone renders it
probable that in most cases they
are connected with the act of
reproduction. In innumerable
instances these characters are
fully developed only at maturity,
and often during only a part
of the year, which is always
the breeding-season. The males
(passing over a few exceptional
cases) are the more active in
courtship; they are the better
armed, and are rendered the more
attractive in various ways. It
is to be especially observed
that the males display their
attractions with elaborate care
in the presence of the females;
and that they rarely or never
display them excepting during
the season of love. It is incredible
that all this should be purposeless.
Lastly we have distinct evidence
with some quadrupeds and birds,
that the individuals of one sex
are capable of feeling a strong
antipathy or preference for certain
individuals of the other sex.
Bearing in mind these facts,
and the marked results of man's
unconscious selection, when applied
to domesticated animals and cultivated
plants, it seems to me almost
certain that if the individuals
of one sex were during a long
series of generations to prefer
pairing with certain individuals
of the other sex, characterised
in some peculiar manner, the
offspring would slowly but surely
become modified in this same
manner. I have not attempted
to conceal that, excepting when
the males are more numerous than
the females, or when polygamy
prevails, it is doubtful how
the more attractive males succeed
in leaving a large number of
offspring to inherit their superiority
in ornaments or other charms
than the less attractive males;
but I have shewn that this would
probably follow from the females,-
especially the more vigorous
ones, which would be the first
to breed,- preferring not only
the more attractive but at the
same time the more vigorous and
victorious males.
Although we have some positive
evidence that birds appreciate
bright and beautiful objects,
as with the bower-birds of Australia,
and although they certainly appreciate
the power of song, yet I fully
admit that it is astonishing
that the females of many birds
and some mammals should be endowed
with sufficient taste to appreciate
ornaments, which we have reason
to attribute to sexual selection;
and this is even more astonishing
in the case of reptiles, fish,
and insects. But we really know
little about the minds of the
lower animals. It cannot be supposed,
for instance, that male birds
of paradise or peacocks should
take such pains in erecting,
spreading, and vibrating their
beautiful plumes before the females
for no purpose. We should remember
the fact given on excellent authority
in a former chapter, that several
peahens, when debarred from an
admired male, remained widows
during a whole season rather
than pair with another bird.
Nevertheless I know of no fact
in natural history more wonderful
than that the female Argus pheasant
should appreciate the exquisite
shading of the ball-and-socket
ornaments and the elegant patterns
on the wing-feather of the male.
He who thinks that the male was
created as he now exists must
admit that the great plumes,
which prevent the wings from
being used for flight, and which
are displayed during courtship
and at no other time in a manner
quite peculiar to this one species,
were given to him as an ornament.
If so, he must likewise admit
that the female was created and
endowed with the capacity of
appreciating such ornaments.
I differ only in the conviction
that the male Argus pheasant
acquired his beauty gradually,
through the preference of the
females during many generations
for the more highly ornamented
males; the aesthetic capacity
of the females having been advanced
through exercise or habit, just
as our own taste is gradually
improved. In the male through
the fortunate chance of a few
feathers being left unchanged,
we can distinctly trace how simple
spots with a little fulvous shading
on one side may have been developed
by small steps into the wonderful
ball-and-socket ornaments; and
it is probable that they were
actually thus developed.
Everyone who admits the principle
of evolution, and yet feels great
difficulty in admitting that
female mammals, birds, reptiles,
and fish, could have acquired
the high taste implied by the
beauty of the males, and which
generally coincides with our
own standard, should reflect
that the nerve-cells of the brain
in the highest as well as in
the lowest members of the vertebrate
series, are derived from those
of the common progenitor of this
great kingdom. For we can thus
see how it has come to pass that
certain mental faculties, in
various and widely distinct groups
of animals, have been developed
in nearly the same manner and
to nearly the same degree.
The reader who has taken the
trouble to go through the several
chapters devoted to sexual selection,
will be able to judge how far
the conclusions at which I have
arrived are supported by sufficient
evidence. If he accepts these
conclusions he may, I think,
safely extend them to mankind;
but it would be superfluous here
to repeat what I have so lately
said on the manner in which sexual
selection apparently has acted
on man, both on the male and
female side, causing the two
sexes to differ in body and mind,
and the several races to differ
from each other in various characters,
as well as from their ancient
and lowly-organised progenitors.
He who admits the principle
of sexual selection will be led
to the remarkable conclusion
that the nervous system not only
regulates most of the existing
functions of the body, but has
indirectly influenced the progressive
development of various bodily
structures and of certain mental
qualities. Courage, pugnacity,
perseverance, strength and size
of body, weapons of all kinds,
musical organs, both vocal and
instrumental, bright colours
and ornamental appendages, have
all been indirectly gained by
the one sex or the other, through
the exertion of choice, the influence
of love and jealousy, and the
appreciation of the beautiful
in sound, colour or form; and
these powers of the mind manifestly
depend on the development of
the brain.
Man scans with scrupulous care
the character and pedigree of
his horses, cattle, and dogs
before he matches them; but when
he comes to his own marriage
he rarely, or never, takes any
such care. He is impelled by
nearly the same motives as the
lower animals, when they are
left to their own free choice,
though he is in so far superior
to them that he highly values
mental charms and virtues. On
the other hand he is strongly
attracted by mere wealth or rank.
Yet he might by selection do
something not only for the bodily
constitution and frame of his
offspring, but for their intellectual
and moral qualities. Both sexes
ought to refrain from marriage
if they are in any marked degree
inferior in body or mind; but
such hopes are Utopian and will
never be even partially realised
until the laws of inheritance
are thoroughly known. Everyone
does good service, who aids towards
this end. When the principles
of breeding and inheritance are
better understood, we shall not
hear ignorant members of our
legislature rejecting with scorn
a plan for ascertaining whether
or not consanguineous marriages
are injurious to man.
The advancement
of the welfare of mankind is
a most intricate
problem: all ought to refrain
from marriage who cannot avoid
abject poverty for their children;
for poverty is not only a great
evil, but tends to its own increase
by leading to recklessness in
marriage. On the other hand,
as Mr. Galton has remarked, if
the prudent avoid marriage, whilst
the reckless marry, the inferior
members tend to supplant the
better members of society. Man,
like every other animal, has
no doubt advanced to his present
high condition through a struggle
for existence consequent on his
rapid multiplication; and if
he is to advance still higher,
it is to be feared that he must
remain subject to a severe struggle.
Otherwise he would sink into
indolence, and the more gifted
men would not be more successful
in the battle of life than the
less gifted. Hence our natural
rate of increase, though leading
to many and obvious evils, must
not be greatly diminished by
any means. There should be open
competition for all men; and
the most able should not be prevented
by laws or customs from succeeding
best and rearing the largest
number of offspring. Important
as the struggle for existence
has been and even still is, yet
as far as the highest part of
man's nature is concerned there
are other agencies more important.
For the moral qualities are advanced,
either directly or indirectly,
much more through the effects
of habit, the reasoning powers,
instruction, religion, &c., than
through natural selection; though
to this latter agency may be
safely attributed the social
instincts, which afforded the
basis for the development of
the moral sense.
The main conclusion arrived
at in this work, namely, that
man is descended from some lowly
organised form, will, I regret
to think, be highly distasteful
to many. But there can hardly
be a doubt that we are descended
from barbarians. The astonishment
which I felt on first seeing
a party of Fuegians on a wild
and broken shore will never be
forgotten by me, for the reflection
at once rushed into my mind-
such were our ancestors. These
men were absolutely naked and
bedaubed with paint, their long
hair was tangled, their mouths
frothed with excitement, and
their expression was wild, startled,
and distrustful. They possessed
hardly any arts, and like wild
animals lived on what they could
catch; they had no government,
and were merciless to every one
not of their own small tribe.
He who has seen a savage in his
native land will not feel much
shame, if forced to acknowledge
that the blood of some more humble
creature flows in his veins.
For my own part I would as soon
be descended from that heroic
little monkey, who braved his
dreaded enemy in order to save
the life of his keeper, or from
that old baboon, who descending
from the mountains, carried away
in triumph his young comrade
from a crowd of astonished dogs-
as from a savage who delights
to torture his enemies, offers
up bloody sacrifices, practices
infanticide without remorse,
treats his wives like slaves,
knows no decency, and is haunted
by the grossest superstitions.
Man may be excused for feeling
some pride at having risen, though
not through his own exertions,
to the very summit of the organic
scale; and the fact of his having
thus risen, instead of having
been aboriginally placed there,
may give him hope for a still
higher destiny in the distant
future. But we are not here concerned
with hopes or fears, only with
the truth as far as our reason
permits us to discover it; and
I have given the evidence to
the best of my ability. We must,
however, acknowledge, as it seems
to me, that man with all his
noble qualities, with sympathy
which feels for the most debased,
with benevolence which extends
not only to other men but to
the humblest living creature,
with his god-like intellect which
has penetrated into the movements
and constitution of the solar
system- with all these exalted
powers- Man still bears in his
bodily frame the indelible stamp
of his lowly origin.
SUPPLEMENTAL NOTE.
ON SEXUAL SELECTION IN RELATION
TO MONKEYS.
Reprinted from NATURE, November
2, 1876, p. 18.
IN the discussion
on Sexual Selection in my Descent
of Man,
no case interested and perplexed
me so much as the brightly-coloured
hinder ends and adjoining parts
of certain monkeys. As these
parts are more brightly coloured
in one sex than the other, and
as they become more brilliant
during the season of love, I
concluded that the colours had
been gained as a sexual attraction.
I was well aware that I thus
laid myself open to ridicule;
though in fact it is not more
surprising that a monkey should
display his bright-red hinder
end than that a peacock should
display his magnificent tail.
I had, however, at that time
no evidence of monkeys exhibiting
this part of their bodies during
their courtship; and such display
in the case of birds affords
the best evidence that the ornaments
of the males are of service to
them by attracting or exciting
the females. I have lately read
an article by Joh. von Fischer,
of Gotha, published in Der Zoologische
Garten, April, 1876, on the expression
of monkeys under various emotions,
which is well worthy of study
by any one interested in the
subject, and which shews that
the author is a careful and acute
observer. In this article there
is an account of the behaviour
of a young male mandrill when
he first beheld himself in a
looking-glass, and it is added,
that after a time he turned round
and presented his red hinder
end to the glass. Accordingly
I wrote to Herr J. von Fischer
to ask what he supposed was the
meaning of this strange action,
and he has sent me two long letters
full of new and curious details,
which will, I hope, be hereafter
published. He says that he was
himself at first perplexed by
the above action, and was thus
led carefully to observe several
individuals of various other
species of monkeys, which he
has long kept in his house. He
finds that not only the mandrill
(Cynocephalus mormon) but the
drill (C. leucophaeus) and three
other kinds of baboons (C. hamadryas,
sphinx, and babouin), also Cynopithecus
niger, and Macacus rhesus and
nemestrinus, turn this part of
their bodies, which in all these
species is more or less brightly
coloured, to him when they are
pleased, and to other persons
as a sort of greeting. He took
pains to cure a Macacus rhesus,
which he had kept for five years,
of this indecorous habit, and
at last succeeded. These monkeys
are particularly apt to act in
this manner, grinning at the
same time, when first introduced
to a new monkey, but often also
to their old monkey friends;
and after this mutual display
they begin to play together.
The young mandrill ceased spontaneously
after a time to act in this manner
towards his master, von Fischer,
but continued to do so towards
persons who were strangers and
to new monkeys. A young Cynopithecus
niger never acted, excepting
on one occasion, in this way
towards his master, but frequently
towards strangers, and continues
to do so up to the present time.
From these facts von Fischer
concludes that the monkeys which
behaved in this manner before
a looking-glass (viz., the mandrill,
drill, Cynopithecus niger, Macacus
rhesus and nemestrinus) acted
as if their reflection were a
new acquaintance. The mandrill
and drill, which have their hinder
ends especially ornamented, display
it even whilst quite young, more
frequently and more ostentatiously
than do the other kinds. Next
in order comes Cynocephalus hamadryas,
whilst the other species act
in this manner seldomer. The
individuals, however, of the
same species vary in this respect,
and some which were very shy
never displayed their hinder
ends. It deserves especial attention
that von Fischer has never seen
any species purposely exhibit
the hinder part of its body,
if not at all coloured. This
remark applies to many individuals
of Macacus cynomolgus and Cercocebus
radiatus (which is closely allied
to M. rhesus), to three species
of Cercopithecus and several
American monkeys. The habit of
turning the hinder ends as a
greeting to an old friend or
new acquaintance, which seems
to us so odd, is not really more
so than the habits of many savages,
for instance that of rubbing
their bellies with their hands,
or rubbing noses together. The
habit with the mandrill and drill
seems to be instinctive or inherited,
as it was followed by very young
animals; but it is modified or
guided, like so many other instincts,
by observation, for von Fischer
says that they take pains to
make their display fully; and
if made before two observers,
they turn to him who seems to
pay the most attention.
With respect
to the origin of the habit,
von Fischer remarks
that his monkeys like to have
their naked hinder ends patted
or stroked, and that they then
grunt with pleasure. They often
also turn this part of their
bodies to other monkeys to have
bits of dirt picked off, and
so no doubt it would be with
respect to thorns. But the habit
with adult animals is connected
to a certain extent with sexual
feelings, for von Fischer watched
through a glass door a female
Cynopithecus niger, and she during
several days, "umdrehte und dem
Mannchen mit gurgelnden Tonen
die stark gerothete Sitzflache
zeigte, was ich fruher nie an
diesem Thier bemerkt hatte. Beim
Anblick dieses Gegenstandes erregte
sich das Mannchen sichtlich,
denn es polterte heftig an den
Staben, ebenfalls gurgelnde Laute
ausstossend." As all the monkeys
which have the hinder parts of
their bodies more or less brightly
coloured live, according to von
Fischer, in open rocky places,
he thinks that these colours
serve to render one sex conspicuous
at a distance to the other; but,
as monkeys are such gregarious
animals, I should have thought
that there was no need for the
sexes to recognise each other
at a distance. It seems to me
more probable that the bright
colours, whether on the face
or hinder end, or, as in the
mandrill, on both, serve as a
sexual ornament and attraction.
Anyhow, as we now know that monkeys
have the habit of turning their
hinder ends towards other monkeys,
it ceases to be at all surprising
that it should have been this
part of their bodies which has
been more or less decorated.
The fact that it is only the
monkeys thus characterised which,
as far as at present known, act
in this manner as a greeting
towards other monkeys renders
it doubtful whether the habit
was first acquired from some
independent cause, and that afterwards
the parts in question were coloured
as a sexual ornament; or whether
the colouring and the habit of
turning round were first acquired
through variation and sexual
selection, and that afterwards
the habit was retained as a sign
of pleasure or as a greeting,
through the principle of inherited
association. This principle apparently
comes into play on many occasions:
thus it is generally admitted
that the songs of birds serve
mainly as an attraction during
the season of love, and that
the leks, or great congregations
of the black-grouse, are connected
with their courtship; but the
habit of singing has been retained
by some birds when they feel
happy, for instance by the common
robin, and the habit of congregating
has been retained by the black-grouse
during other seasons of the year.
I beg leave to refer to one
other point in relation to sexual
selection. It has been objected
that this form of selection,
as far as the ornaments of the
males are concerned, implies
that all females within the same
district must possess and exercise
exactly the same taste. It should,
however, be observed, in the
first place, that although the
range of variation of a species
may be very large, it is by no
means indefinite. I have elsewhere
given a good instance of this
fact in the pigeon, of which
there are at least a hundred
varieties differing widely in
their colours, and at least a
score of varieties of the fowl
differing in the same kind of
way; but the range of colour
in these two species is extremely
distinct. Therefore the females
of natural species cannot have
an unlimited scope for their
taste. In the second place, I
presume that no supporter of
the principle of sexual selection
believes that the females select
particular points of beauty in
the males; they are merely excited
or attracted in a greater degree
by one male than by another,
and this seems often to depend,
especially with birds, on brilliant
colouring. Even man, excepting
perhaps an artist, does not analyse
the slight differences in the
features of the woman whom he
may admire, on which her beauty
depends. The male mandrill has
not only the hinder end of his
body, but his face gorgeously
coloured and marked with oblique
ridges, a yellow beard, and other
ornaments. We may infer from
what we see of the variation
of animals under domestication,
that the above several ornaments
of the mandrill were gradually
acquired by one individual varying
a little in one way, and another
individual in another way. The
males which were the handsomest
or the most attractive in any
manner to the females would pair
oftenest, and would leave rather
more offspring than other males.
The offspring of the former,
although variously intercrossed,
would either inherit the peculiarities
of their fathers or transmit
an increased tendency to vary
in the same manner. Consequently
the whole body of males inhabiting
the same country would tend from
the effects of constant intercrossing
to become modified almost uniformly,
but sometimes a little more in
one character and sometimes in
another, though at an extremely
slow rate; all ultimately being
thus rendered more attractive
to the females. The process is
like that which I have called
unconscious selection by man,
and of which I have given several
instances. In one country the
inhabitants value a fleet or
light dog or horse, and in another
country a heavier and more powerful
one; in neither country is there
any selection of individual animals
with lighter or stronger bodies
and limbs; nevertheless after
a considerable lapse of time
the individuals are found to
have been modified in the desired
manner almost uniformly, though
differently in each country.
In two absolutely distinct countries
inhabited by the same species,
the individuals of which can
never during long ages have intermigrated
and intercrossed, and where,
moreover, the variations will
probably not have been identically
the same, sexual selection might
cause the males to differ. Nor
does the belief appear to me
altogether fanciful that two
sets of females, surrounded by
a very different environment,
would be apt to acquire somewhat
different tastes with respect
to form, sound, or colour. However
this may be, I have given in
my Descent of Man instances of
closely-allied birds inhabiting
distinct countries, of which
the young and the females cannot
be distinguished, whilst the
adult males differ considerably,
and this may be attributed with
much probability to the action
of sexual selection.
THE END . |
