"It seemed to me sufficient to indicate, in the first edition of my 'Origin of Species,' that by this work "light would be thrown on the origin of man and his history;" and this implies that man must be included with other organic beings in any general conclusion respecting his manner of appearance on this earth."
"The sole object of this work is to consider, firstly, whether man, like every other species, is descended from some pre-existing form; secondly, the manner of his development; and thirdly, the value of the differences between the so-called races of man."
"It has often and confidently
been asserted, that man's origin can never be known: but
ignorance more frequently
begets confidence than does knowledge: it is those who know little,
and not those who know much, who so positively assert that this or that
problem will never be solved by science. The conclusion that man
is the co-descendant with other species of some ancient, lower, and extinct
form, is not in any degree new."
"During many years it has seemed to me highly probable that sexual selection has played an important part in differentiating the races of man."
1. EVIDENCE OF THE DESCENT OF MAN FROM SOME LOWER FORM
"He who wishes to decide
whether man is the modified descendant of some pre-existing form, would
probably first enquire whether man varies, however slightly, in bodily
structure and in mental faculties; and if so, whether the variations are
transmitted to his offspring in accordance with the laws which prevail
with the lower animals. Again, are the variations the
result, as far as
our ignorance permits us to judge, of the same general causes, and are
they governed by the same general laws, as in the case of other organisms;
for instance, by correlation, the inherited effects of use and disuse,
etc.?
It might also naturally
be enquired whether man, like so many other animals, has given rise to
varieties and sub-races, differing but slightly from each other, or to
races differing so much that they must be classed as doubtful species?
How are such races distributed over the
world; and how, when
crossed, do they react on each other in the first and succeeding generations?"
"The enquirer would next come to the important point, whether man tends to increase at so rapid a rate, as to lead to occasional severe struggles for existence; and consequently to beneficial variations, whether in body or mind, being preserved, and injurious ones eliminated. Do the races or species of men, whichever term may be applied, encroach on and replace one another, so that some finally become extinct?"
"It is notorious that man is constructed on the same general type or model as other mammals. All the bones in his skeleton can be compared with corresponding bones in a monkey, bat, or seal. So it is with his muscles, nerves, blood-vessels and internal viscera. The brain, the most important of all the organs, follows the same law. Man is liable to receive from the lower animals, and to communicate to them, certain diseases; and this fact proves the close similarity."
"Man is infested with internal parasites, sometimes causing fatal effects; and is plagued by external parasites, all of which belong to the same genera or families as those infesting other mammals, and in the case of scabies to the same species."
"Man differs conspicuously
from all the other primates in being almost naked. But a few short
straggling hairs are found over the greater part of the body in the man,
and fine down on that of the woman. The different races differ much
in hairiness; and in the individuals of the same race the hairs are highly
variable, not only in abundance, but likewise in position:
There can be little
doubt that the hairs thus scattered over the body are the rudiments of
the uniform hairy coat of the lower animals."
"The bearing of the
three great classes of facts now given is unmistakeable. But it would be
superfluous fully to recapitulate the line of argument given in detail
in my 'Origin of Species.' The homological construction of the whole
frame in the members of the same class is intelligible, if we admit their
descent from a common progenitor, together with their
subsequent adaptation
to diversified conditions. On any other view, the similarity of pattern
between the hand of a man or monkey, the foot of a horse, the flipper of
a seal, the wing of a bat, etc., is utterly inexplicable."
"Thus we can understand how it has come to pass that man and all other vertebrate animals have been constructed on the same general model, why they pass through the same early stages of development, and why they retain certain rudiments in common. Consequently we ought frankly to admit their community of descent: to take any other view, is to admit that our own structure, and that of all the animals around us, is a mere snare laid to entrap our judgment."
2. ON THE MANNER OF DEVELOPMENT OF MAN FROM SOME LOWER FORM
"It is manifest that man is now subject to much variability. No two individuals of the same race are quite alike. We may compare millions of faces, and each will be distinct. There is an equally great amount of diversity in the proportions and dimensions of the various parts of the body; the length of the legs being one of the most variable points."
"In another and much
more important respect, man differs widely from any strictly domesticated
animal; for his breeding has never long been controlled, either by methodical
or unconscious selection. No race or body of men has been so completely
subjugated by other men, as that certain individuals should be preserved,
and thus unconsciously selected, from somehow excelling in utility to their
masters. Nor have certain male and female individuals been intentionally
picked out and matched, except in the well-known case of the Prussian grenadiers;
and in this case man obeyed, as might have been expected, the
law of methodical
selection; for it is asserted that many tall men were reared in the villages
inhabited by the grenadiers and their tall wives. In Sparta, also, a form
of selection was followed, for it was enacted that all children should
be examined shortly after birth; the well-formed and vigorous being preserved,
the others left to perish."
"If we consider all the races of man as forming a single species, his range is enormous; but some separate races, as the Americans and Polynesians, have very wide ranges. It is a well-known law that widely-ranging species are much more variable than species with restricted ranges; and the variability of man may with more truth be compared with that of widely- ranging species, than with that of domesticated animals."
"Civilised populations have been known under favourable conditions, as in the United States, to double their numbers in twenty-five years; and, according to a calculation, by Euler, this might occur in a little over twelve years. (57. See the ever memorable 'Essay on the Principle of Population,' by the Rev. T. Malthus, vol. i. 1826. pp. 6, 517.) At the former rate, the present population of the United States (thirty millions), would in 657 years cover the whole terraqueous globe so thickly, that four men would have to stand on each square yard of surface. The primary or fundamental check to the continued increase of man is the difficulty of gaining subsistence, and of living in comfort. We may infer that this is the case from what we see, for instance, in the United States, where subsistence is easy, and there is plenty of room. If such means were suddenly doubled in Great Britain, our number would be quickly doubled. With civilised nations this primary check acts chiefly by restraining marriages. The greater death-rate of infants in the poorest classes is also very important; as well as the greater mortality, from various diseases, of the inhabitants of crowded and miserable houses, at all ages. The effects of severe epidemics and wars are soon counterbalanced, and more than counterbalanced, in nations placed under favourable conditions. Emigration also comes in aid as a temporary check, but, with the extremely poor classes, not to any great extent."
"Malthus has discussed these several checks, but he does not lay stress enough on what is probably the most important of all, namely infanticide, especially of female infants, and the habit of procuring abortion. These practices now prevail in many quarters of the world; and infanticide seems formerly to have prevailed on a still more extensive scale."
"We have now seen that
man is variable in body and mind; and that the variations are induced,
either directly or indirectly, by the same general causes, and obey the
same general laws, as with the lower animals. Man has spread widely
over the face of the earth, and must have been exposed, during his incessant
migrations to the most diversified conditions.
The inhabitants of
Tierra del Fuego, the Cape of Good Hope, and Tasmania in the one hemisphere,
and of the arctic regions in the other, must have passed through many climates,
and changed their habits many times, before they reached their present
homes.
The early progenitors
of man must also have tended, like all other animals, to have increased
beyond their means of subsistence; they must, therefore, occasionally have
been exposed to a struggle for existence, and consequently to the rigid
law of natural selection. Beneficial variations of all kinds will
thus, either occasionally or habitually, have been preserved and injurious
ones eliminated."
3. COMPARISON OF MENTAL POWERS
"The formation of different languages and of distinct species, and the proofs that both have been developed through a gradual process, are curiously parallel."
21. SUMMARY AND CONCLUSION
"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."
"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."
"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 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."
"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."
"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, etc., 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."
"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."
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You can download a complete version of 'Descent' from Project Gutenburg.
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