The object of this lecture is to explain, with as much
simplicity as possible, the opinions of Darwin on the
chain of secondary causes which has resulted in the
wonderful structures known to us as living creatures,
and including, in an almost infinite variety, lichen and
moss, mite and mildew, grass and flower and branching
tree; mollusk and reptile and fish; the swan, the
petrel, the ostrich and the eagle; the cunning ape;
the faithful hound; the elephant, sagacious and mindful
of insults; the lion, capable of generosity; the
horse, patient of labours and eager for victory; and,
along with a multitude of others diversely qualified,
One, without doubt partaking of the animal nature
that lives and dies, yet seeming to partake of something
beyond it, seeming to be distinguished from all
the rest by its postures, by its laughing, by its cooking
its food, by its articulate language, by its powers of
reasoning; and yet linked and united to its inferiors by
a multitude of affinities and sympathies, resemblances
of form and nature, and by the very details of its superiority.
So ran the Pagan legend that Providence had
compacted man’s moral nature out of particles taken
from each of the lower animals, giving him the wisdom
of the serpent and the fiery courage of the lion3. To
this sense of an intimate union between man and the
rest of the animate creation have the writers of fables
in all ages appealed, while imparting their lessons of
prudence and virtue under the guise of transactions
between birds and beasts and trees of the forest.
It is well known that after the discovery of almost
every great truth a sort of feeling or instinct of it
can be traced back in obscure hints, in chance expressions,
in vague guesses, in flights of imagination, so
that people very soon begin to fancy that they have
all along understood and maintained the very theory,
which, on its first appearance, they violently rejected
as something false and even vicious. Darwinism has
this characteristic of truth, that it has often been
obscurely anticipated. It has this other characteristic,
that its fiercest opponents have already begun insensibly
to adopt its conclusions, and to speak its language, to
opine, even, that the credit of its promulgation belongs
to themselves.
In Mr. Darwin’s own historical sketch of the rise and
progress of his doctrine, he does full justice to those
who have preceded and who have worked with him in
bringing it to light and in establishing its foundations.
The opinion that species originate, not by successive
miraculous interpositions or acts of creation, but by
birth, was held as far back as 1794–5, by four men of
distinguished genius, by Lamarck, by Mr. Darwin’s
own grandfather, Dr. Erasmus Darwin, by Geoffroy
Saint Hilaire, and by the poet Goethe. In the present
day, Mr. Wallace, Mr. Herbert Spencer, the great
zoologist Van Baer, and others, independently of Mr.
Darwin, seem to have come more or less to the same
conclusions, which have been warmly espoused and
powerfully vindicated by Dr. Hooker, Professor Huxley,
and Sir Charles Lyell. I mention these names because
it seems to be their due, and not for the sake of giving
weight to any argument because of the scientific renown
of its advocates; there are names, it may be, equally
distinguished on the opposite side. But one thing ought
to be observed, that the progress of scientific enquiry
has achieved so much during the last hundred years
that the opinions of the older Naturalists have an importance
when they agree with modern conclusions,
which they cannot have when they differ from them,
unless it can be shown that the observations, the experiments,
the discoveries of late years had all been made
by, or were known to, the earlier enquirers. For those,
however, who think the opinions of a past generation
of necessity more trustworthy than those of the present,
Sir Charles Lyell has done well to point out that
Linnæus himself looked forward to a time when it
should be proved that in botany, at least, all species of
a genus had descended from the same mother4.
This is precisely Mr. Darwin’s opinion on the origin
of species at large. He applies it to the animal as well
as to the vegetable kingdom. He extends it by considering
genera themselves as species of the orders which
contain them, and orders as species of the great classes
to which they as orders respectively belong. In a word,
he considers that all living forms whatsoever are descended
from a very few original ancestors of the
simplest type, and that this primæval group itself had,
probably, a common parentage. Wildly improbable,
ludicrously absurd, degrading to humanity, and irreligious,
no doubt this hypothesis has appeared to
many, and will continue so to appear till it has been
studied with attention, and studied without prejudice.
To rescue it from the prejudice which would make it
in the eyes of some a pernicious and forbidden study,
is the hope which underlies the object of the present
lecture.
Round Nelson’s Column in Trafalgar Square there
are four colossal statue lions, the conception of a great
artist. They look unnatural, not because of their size,
or their position, or the material of which they are
made, but because they are all so exactly alike; and
exact likenesses are scarcely ever found in animate
nature, unless it be among the very simplest organisms.
When we speak of a striking likeness between two
human beings, we evidently imply that a high degree
of similarity is uncommon, and, therefore, noteworthy.
What is true of even the most highly organized animals,
is true, as far as observation goes, of all below them.
Horses, dogs, sheep, kine, afford familiar illustrations
of this principle. To the uneducated eye, individual
differences may be totally unapparent, which are yet
perfectly conspicuous to the trainer, the huntsman, the
shepherd, and the drover. Wild creatures know their
mates; wild herds select their leaders; the bee and the
ant are capable of distinguishing the various individuals
of their own communities, for strangers of the very self-same
species with themselves they repel or destroy5.
As each creature is, in numberless cases, the offspring
of two unlike parents, it cannot be an exact copy of
either, and the influences of the two parents may be
combined in various proportions in each of the offspring;
but the parents themselves are continually changing,
with the variations of age and food and climate, so that
the very rule of resemblance between the producers and
the produced will entail another rule of unlikeness
between the several members of an offspring not born
all at once.
It is a fact, which cannot be denied, that in numberless
instances the young of a creature differ more or
less from the parents and likewise among themselves.
Why it should be so has been in part explained. This
is the Variability, without which Natural Selection could
never have been thought of, because without differences
there would have been nothing to select. But this
Variability being granted, the Darwinian theory becomes
possible—becomes quite capable of referring
back the elephant and the pig, for instance, to the
same ancestry. The difference between progenitors and
their immediate offspring are, it is true, comparatively
slight. It would, indeed, be a prodigious birth if one
family contained at once a young monkey, a little pig,
a big donkey, and a great goose; but it is obviously
possible that any amount of unlikeness may be found
between the descendants of common ancestors, if we are
not confined to the differences of a single generation,
but are allowed to multiply them through as many
thousands as we require. Say that two race-courses
differ in length by one yard; multiply that difference
1760 times and they will then differ by a whole mile.
If, on leaving this Lecture-room, you found the trees—which
half-an-hour ago were bare and leafless—clothed
with summer verdure, your gardens blooming with a
wealth of roses, your orchards laden with autumnal
fruits, you would scarcely credit your senses; and yet,
when the requisite number of half-hours, reckoned by
days and months, shall have elapsed, you will greet
these wonderful changes as perfectly natural and nothing
to be wondered at. In a dissolving view that is well
managed, Alpine peak and glacier-pass melt imperceptibly
into some tall cathedral and sunshiny market-place.
The two scenes are wholly unlike, and yet it is
contrived that at no moment should the passage from
one to the other be discernibly abrupt. Is it not
possible then to conceive that through an immense
multitude of generations the form of an ape might be
derived from the form of a fish? We do not mean to
say that this has actually happened, but supposing the
descendant of the fish to vary continuously in the direction
of the ape-like form, the result would be intelligible
enough. What, then, is there to determine variation in
any particular direction, and what limits are there, if
any, to the system of interminable change which the
principle of variation seems to involve?
Of course it is understood that the general mass of
characters or qualities belonging to any creature are
inherited by one generation from its immediate ancestors
and transmitted to its immediate descendants, so that
for a long period there would be a large number of
individuals in the world united into a group by
common characters, which according to their supposed
importance we might call specific or generic. But
besides this, there is the very curious principle of Reversion
to be taken into account, as largely conducing
to the comparative permanence of species. In Norway,
I believe, when the father’s name is Jack, and the
son’s name is Tom, Tom is called Tom Jackson, and
Tom is in the habit of giving his own eldest son the
grandfather’s name, and then Tom Jackson’s son is
called Jack Tomson. Now, in the same way, in nature
it not unfrequently happens that when a long-nosed
man is father of a short-nosed son, the son of the
short-nosed man inherits by reversion the more elongated
feature of his grandsire. Under certain conditions,
which however greatly limit it, the operation
of this principle of Reversion may extend, so far as
we know, to any quality whatever after an interval of
any number of generations. The tendency, therefore,
is to the permanence of species, and yet, as will be
shown in the sequel, it has furnished Mr. Darwin with
an additional argument to prove that species are not
permanent. It must be borne in mind that when a
character reverts from a very distant ancestor, the
creature which inherits it will have numerous other
qualities, all probably more or less differing from those
originally united to the reversionary character; just as
if, in the School of Art, a picture by Raffaelle were
shown to fifty pupils, and when it had been copied by
the first, the second pupil were to make a copy of the
copy, and so on to the end, each of the copies would
no doubt differ more and more from the original, and
yet in the very last, by the help of memory or sympathetic
genius, there might be some beauty not to
be found in any of the others, recalling the hand of
the great master; while it is true, that if the sketch
were something exceedingly simple, the fiftieth copy,
and all the intermediate ones, might be almost exactly
like the original; and so in nature, exceedingly simple
organisms are seemingly reproduced for almost endless
generations with no change, or scarcely any.
If it be true that all living creatures on this earth
spring from a very few, extremely simple, original
germs of life, we have to explain how it is that now
there is an enormous variety of highly organised creatures,
and at the same time some of extreme simplicity.
For, if the simplest forms are permanent, how can the
more complex be derived from them? On the other
hand, if the simplest forms vary, how is it that we
find, as we do, the very earliest known form of life
still living at the present day? The solution is easy
to suggest, that the offspring of very simple forms are
sometimes exactly like their parents, and sometimes
not exactly like. From what has been said above of
Inheritance and Variation, this is in the highest degree
probable, and, this being admitted, it will follow that according
to circumstances the progeny that are like their
parents, or those that are unlike, will have the best of
it. Why this follows will now have to be explained.
All over the surface of our globe there is a struggle
for life going on. The instinct of self-preservation
is probably stronger than any other, so that we may
rely upon it that the creatures of every race will strive
to preserve their own existence, if need be, at the
expense of that of others. It may be horrible to
the sentimentalist, but it is true; and remember that
man as well as the tiger is a carnivorous mammal.
There is no beast or bird of prey that can be compared
with man for his ravaging, destructive, butchering, remorseless
dissipation of other forms of life, to preserve
his own existence and make it comfortable. He secures
his gluttony from famine, as far as he can, by being
omnivorous. Moss and fungus, grass and herb, leaf
and flower and stem and fruit, all alike find a grave in
man. The lion and the flea are the victims of his fear;
many a harmless snake and toad of his antipathy; the
otter and the fox die for his sport; the ostrich and the
ermine for his vanity. For his food, like a wolf, he
slays the harmless sheep; like a hawk, he pounces
on the innocent chicken; like a wily panther, surprises
the antlered stag; devours fish like a shark; spreads
nets for his prey like a spider; and in some instances
acquires a well-developed taste for the flesh of his
fellow-man. Practically with all living animals, the
first consideration is food. If all living animals could
obtain abundance of pleasant and suitable food without
preying on one another, the scene of war which Nature
presents would perhaps in a great measure disappear.
Yet this warfare is as conspicuous in the vegetable as
it is in the animal kingdom. There is a certain amount
of nourishment in a given piece of ground, and for
that nourishment the plants upon it will compete, some
thriving and multiplying to the hindrance and destruction
of the others. Here again, if the surface
of the globe supplied nutriment for all its plants,
there would be at least no need for this destructive competition.
And how is it that this wide, wide world does not
supply food enough for all the vegetable forms that
make an effort to live upon it? The answer to this
curious question has long been known, though not
sufficiently attended to. It would not be fair to say
that Nature is stingy in her supplies of food, but
rather that she is too generously prolific of forms of
life. For, take the supposition that all living creatures,
whether animal or vegetable, were shielded from all
enemies and influences at present hurtful to them, and
let us see to what it would bring us. A single grain
of wheat produces an ear containing ten, twenty, or
some larger number of grains. But if the ear contained
only two grains, still, at that rate of increase,
a single grain would in thirty years be represented by
more than a thousand millions of grains6. What, then,
would be the position of the world, if, starting with a
thousand millions of grains, this rate of increase were
allowed to continue unchecked, not for thirty years,
but for three thousand? But Mr. Darwin has calculated
in regard to the elephant, which is reckoned the
slowest breeder of all known animals, that, according
to the very lowest probable rate of natural increase, a
single pair would in five hundred years have a progeny
of fifteen million living elephants7. Now fancy an
island like our own, only in a climate suitable to
elephants, into which a couple should have found their
way a thousand years back. At the end of five hundred
years, if all that were born were enabled to breed unchecked,
there would be at least fifteen millions of their
huge descendants stalking about the land; but, at the
end of five hundred years more, there would be one
hundred and twelve millions of millions of elephants.
Goodness! What a stupendous menagerie! What a
zoological garden! What a prospect at the end of the
next five hundred years! And all this time, remember,
according to our sentimental, philanthropic, philelephantine,
nature-improving scheme, the men and women,
the donkeys with a soul above thistles, the thistles no
longer toothsome to donkeys, the mice, the rats, the
cats, the oaks, the cabbages, the toadstools, would have
been multiplying, not in the same proportion as the
elephants, but very much more rapidly. The great
desideratum would be standing room. The back of
an elephant, or the branch of an oak, would no doubt
command an enormous rent, and a right of way across
the heads of your neighbours would be religiously
guarded by the law of the land. Nor would the position
of affairs be better in the surrounding sea; for
while these elephants have been computed to breed at
the rate of two young ones in thirty years, a single
codfish has been found to produce in one year more
than six millions of eggs, and there are other creatures
infinitely more prolific8.
You see, then, that the struggle for existence is an
absolute necessity; and out of this all-essential strife
springs what has been well called Natural Selection.
What is meant by this will more easily be understood
by looking first at Artificial Selection, which has been
practised by man, sometimes consciously, and oftener
unconsciously, in the process of domesticating a great
number of plants and animals. Dogs, sheep, bulls, pigs,
horses, fowls, pigeons, cabbages, and other culinary
vegetables, strawberries, and all manner of edible fruits,
together with gay-coloured, curiously-formed, sweetly-perfumed
garden-flowers innumerable, have been, and
are still being, subjected to man’s selection. That the
wonderful changes which occur are indeed due to man’s
repeated choice of the varieties which suit his purposes,
is clear from this, that all the remarkable changes have
taken place in those particular qualities which man
has valued, leaving the other qualities comparatively
unaltered. Let it be speed, size, taste, colour, form,
temper, the coat, the feathers, the flesh, the muscular
strength, the powers of endurance; in a vegetable, let
it be the root, the stem, the leaf, the flower, the fruit,
the seed, let it be what it will that is of value, that
part and that character have been in each case most
highly developed. To take a few examples: You are
fond of peas, and you sow in your garden what your
seedsman tells you are the finest new varieties; you like
strawberries, you admire roses, you fancy a good cabbage,
you are particular about having a mealy potato;
so in each case you plant what you understand to be
the best new kinds. What will you say if it turns out
that the roses have improved in their roots but not in
the bloom, and the potatoes in the bloom but not in
their tubers; that the strawberries have remarkably fine
leaves but very small fruit; that the peas and the
cabbages have indeed enormous stems, while the seed
of the one and the leaf of the other are insignificant
in size and tasteless to the palate? So, too, if you
purchase a race-horse and a pig from the most noted
breeders of those animals, will you not be disgusted
if it turns out that the horse has a remarkable propensity
for fattening, while the pig is distinguished
by nothing but its extreme fleetness of foot? These
disappointments do not occur, because the variations
of domesticated plants and animals are selected by
competent persons. Were strawberry-leaves of as much
importance in horticulture as they are in heraldry, many
fine varieties would soon be exhibited. As soon as the
most minute tendency to vary in any particular direction
has been descried in any living creature, the fancier
can exaggerate the difference to an extent inconceivable
to the inexperienced. As a popular illustration
of this we may take the Big Gooseberry, which fills
so large a space in the newspapers when Parliament
is prorogued. A gooseberry has been grown weighing
more than 37 pennyweights—that is, nearly two ounces9.
But mere size is not a fair test of the extreme plasticity
of living organisms. You may have your trees growing
stiffly upright, or with pendulous branches and prostrate
stems; you may have your cattle long-horned, short-horned,
or with no horns at all; your rabbits straight-eared
or lop-eared; your fowls with every variety of
comb and crest and wattles and plumage; and your
pigeons pretty well at discretion. A type is prefigured,
and the fancier produces it; and what is done for
amusement with pigeons, is done for food, for profit,
for the good of mankind at large, by the grower of
corn, by the breeder of sheep, by all the wise produce-masters
of the world10.
Such is Artificial Selection; but man is after all but
one of Nature’s works, and one of her numerous agents.
All that he does, however miraculous it may seem, can
only be done under her conditions, and by the means
which she supplies. In Artificial Selection man does
but take advantage of the natural laws of Inheritance
and Variation, and while he is seeking by means of
these to produce one alteration, Nature herself is producing
perhaps a hundred others. For, by the law of
Correlation, when one part changes, some other or others
almost inevitably change with it. Whether it be
shortening the beak of a pigeon or lengthening the
neck of a giraffe that is in question, Nature takes care,
along with the change, to make other adaptations of the
structure in the creature’s interest under its altered
circumstances. Surely, the working of this principle
of Correlation indicates a far-sighted Providence of
the results, the disastrous monstrosities, that would
otherwise have sprung from the law of Variation.
Man’s efforts are considerably limited, moreover, by
the law of Reversion. Now, supposing many differing
species to be descended, as we maintain, from common
ancestors, what ought to be the observable effects of this
law? Evidently, we should expect the character of one
species now and then to appear in species allied to it, or
species of kindred origin to vary in the same manner.
In accordance with such an expectation, we find the
horse and the ass sometimes assuming the stripes of
the quagga and the zebra; certain varieties of the
pigeon, the fowl, the turkey, the canary-bird, the duck,
and the goose, all have top-knots or reversed feathers on
their heads; one kind of melon resembles a cucumber in
everything but taste; there are purple-leaved varieties
of the beech and the hazel; and a great multitude of
plants sometimes exhibit their leaves cut, blotched, and
variegated11.
Now, from the working of Nature under, as it were,
man’s guidance, we pass to the working of Nature when
left to her own discretion. The work of Natural Selection
is a very slow and secret work: the slowness of it
veils the movement. As with the hour-hand of a tiny
watch travelling but an inch in a day, there is progress
which you cannot discern, there is change that can be
marked and registered at intervals, though each successive
moment and each successive movement seem to
leave things exactly as they were. You have heard
of the Greek simpleton who had been told that a raven
lived three hundred years, and so bought one to see.
We might live three thousand years instead of three
hundred without being able to prove the theory of
Natural Selection by actual observing. But when a
group of most important observed facts can be explained
consistently by this theory, and by none other, while no
fact has been brought forward to make it inadmissible,
it ought to be accepted till some theory can be produced
equally unimpeachable and explanatory of a larger
group of facts.
Qualities are inherited; but with this peculiarity, that
very generally, and sometimes of necessity, the inheritor
comes into possession of the inherited quality at the
same period of life at which it was acquired by the
parent. As, for instance, the child of a gouty father,
though it may be destined in old age to inherit the
disease, is not born with the gout, any more than a
calf is born with horns, or a cherry-tree produced
covered with cherries. In the life of every creature
there is not merely growth, but development. At
every stage of life it is possible for some quality acquired
by variation to be fixed by Natural Selection.
But in the embryonic and earliest stages of development,
variation is least likely to be of service to any
creature. Such variations, therefore, will less often be
selected than others, and if it be true that many species
have a common ancestry, then it ought to be found that
in their embryonic and earliest stages they resemble one
another. This is precisely what we do find. Plants,
the most remote in appearance and properties when
full grown, differ but slightly in their cotyledons: the
difference between the egg of a nightingale and the egg
of an ostrich bears no proportion to the dissimilarity
between the two birds when fully developed; nor by
comparing the roe of a herring with the roe of a salmon
could you possibly guess, before experience, how the
full-grown fish would differ. But in the life of every
human being there is a stage of development, at which
the most sagacious physician could not distinguish him
from the embryo of a snake, a lizard, a bird, or an ape12.
Now, if the simplest embryonic forms of life were the
progenitors of all existing forms, this is intelligible; but
how else can it be explained?
But, again, if species do not vary, how comes it that
those living at the present day are for the most part
not to be found among the fossil creatures of the ancient
rocks? Well, some will tell you there have been many
distinct creations, following after many catastrophes
potent to destroy all the previous inhabitants of the
globe. Well, I will answer, if you rest on Scripture,
that view has no basis in Scripture, but if you do not
rest on Scripture, it certainly has no scientific foundation,
for though the crust of the globe has been made
what it is almost exclusively by the action of fire and
water, the effect of any sudden convulsions has been
a mere nothing as compared with the results from the
steady, slow-going, ceaselessly-operating forces of those
two agents. Besides, when you look back through the
rocks of different ages, not only do you find some forms
the same in all, which testifies to the permanent unity
of the living creation, but in those forms which differ,
you find the differences increasing the further you go
back, and some forms you find which have no modern
representatives, forms, that is, which have been beaten
in the struggle for existence.
Travel over the globe, and every country will present
you with some new species; distant rivers, distant
islands, in the ocean shallows separated by great deeps,
the opposite sides of a continent, the twin sides of a
mountain chain, the foot, the spur, the knee, the breast,
the snow-clad head of an Alpine range, will all present
you with their own peculiar forms of life. And how
came they there? Created, some will say, in those
regions and for those regions, because of their special
adaptation to them. Yet, since the globe has been
inhabited, vast tracts of it have changed their climates
from tropical heat to frozen gloom, and again, yielded
the thick-ribbed ice to genial suns and fragrant zephyrs.
Unhappy species, the creatures of a fixed idea, created
for the temperate meridian of Devonshire, and condemned
by the thoughtlessness of nature, to pass their
lives in a climate like that of Nova Zembla!
But further, had each species been assigned to its
station as some suppose, by a single act of creation, is
it not reasonable, does not reverence require us to expect,
that each species would have been best off in its own
station? But this is not the case. On the contrary,
imported species of plants and animals often thrive prodigiously
in their new habitat, and over-run it.
Once more, we find in numberless plants and animals
rudimentary organs that are of no use to the possessors,—mammæ,
that give no milk; pistils, in male florets;
in insects wings too small for flight, and soldered to the
wing cases; the fifth toe in the hind-foot of the dog;
the spur of the hen; the wing of the Apteryx; and the
stunted, ineffectual, but ever-present tail in our noble
selves.
On the old theory of creation, in face of these facts,
we cannot save the admired doctrine that nature does
nothing in vain; but on the Darwinian theory of
creation, that doctrine still holds good, and wisdom is
still justified by all her productions; for Natural Selection
works only for the good of a species; it does
not work in vain, or waste its efforts in getting rid
of any organ simply because it is useless, so long as
it is not injurious; it leaves it as it was and where it
was, a germ, a capacity, perhaps, in the future, to be
re-developed or fitted for a new purpose.
Here we have incidentally touched upon what seems
to be morally the grandest part of the whole theory, an
even sublime explanation, as far as it goes, of that small
fraction which we see in terrestrial life of the great and
manifold works of God. We noted above that it is to
death, a necessity much hated, much maligned, that we
owe the possibility of our own birth and standing-room
on the face of the globe; but the theory of Natural
Selection makes it further clear that the causes of death
which we most dread and think evil of—war and famine
and pestilence—are tending continually to improve the
races of living creatures. On the whole, the wisest, the
strongest, the healthiest survive to propagate their
species. In the long run, prudence, courage, and temperance
prevail, and their owners become the parents
of the later generations.
When the competition for life becomes severe, as to
every race of creatures, man included, it does at times
become, the smallest advantageous variation will give
its possessor a superior chance of surviving, while the
smallest that is disadvantageous will diminish the
chance. Take the apposite instance of a number of
quadrupeds incapable of climbing, supported by browsing
on the leaves of trees during a dearth of other
suitable food. When the lower leaves within the
general reach were exhausted, the famine still continuing,
those animals alone would survive which, by
some peculiarity, could reach the higher leaves. In
this way, those that could spring best, those that could
assume even a climbing posture, those endowed with
the longest legs, snouts, or necks, would be selected.
In some such a way, then, we can conceive the jumping
powers of the kangaroo and the antelope, the climbing
powers of the bear and the cat, the trunk of the elephant,
and the long neck of the giraffe to have been evolved
by natural selection. The keen scent of the hound, the
sharp eye of the lynx, the gay colours of the butterfly,
the splendid plumage of the bird of Paradise, are all
easy to account for on this principle of natural selection.
So, too, are the dull colours of many female birds, to
whom obscurity is useful in protecting their young;
so, too, the almost blindness of the mole, which works
in the dark, and to which an instrument at once delicate
and useless, would entail the risk of positive injury.
The principle explains what no other hypothesis has
ever done, not only Nature’s perfection, which, in the
hour of ease, we are ready to believe in, but what has
hitherto been a much greater puzzle to those who knew
of its existence, Nature’s imperfection. The whole creation
is in constant travail to bring forth something
better than its present best. The products of man’s
reason are not, you will readily admit, always perfect,
and yet man’s reason is a part of the creation, and of
nature’s work. The waste of life is prodigious, if such
a term is applicable to the circumstance that often
millions of spores are produced in order that half a
dozen plants may grow; millions of eggs in the roe
of a fish, in order that the parents may be represented
by three or four individuals. The bee defends itself
by its sting, but its weapon of defence is fatal to itself.
Were a merchant habitually to send five or six million
articles of merchandize across the Atlantic on the bare
possibility that five or six articles out of the number
might reach their destination; or, were a father to
arm his son with a weapon on the presumption that
the first time he used it, it would cost him his life;
you would think the man mad, not wise. Yet, if the
astonishing fecundity of the braken, the mushroom, and
the codfish, if the sting of the bee with its backward
serratures, be the products of direct creation, the analogy
is somewhat telling. How different, on the other hand,
must our judgment be of those contrivances, when we
trace them to the simple, primary, beneficent law of
natural selection, working always steadily for the good
of each species, and so working, that we may feel
tolerably sure that when any species dies out and disappears,
it has been replaced by something better. For
by this law, we see that fertility itself is a character
which will be selected as tending to the preservation of
a species, and that many creatures must have acquired
the power of what looks like wasteful reproduction in
the long-continued struggle for existence. We can see,
too, how in that same struggle, it may have proved expedient
for a creature to be armed with a weapon capable
of inspiring terror, yet so contrived that its possessor
should, of necessity, be peaceful towards its neighbours.
True, this might have been done by a single act of
creation, but why, then, was it not done also in the case
of the mosquito, the wasp, and the hornet?
On the theory of sudden creation, how can we account
in any but an arbitrary manner, for the innumerable
cases in which slight differences separate various species;
for the confused neutral ground between different classes,
as where, for example, a creature seems half animal half
plant; for the isolation of many forms from the stations
they are admirably fitted to occupy; for the fact that
many creatures are hideous, weak, timid, violent, and
venomous; for the imperfection of an instinct in one
species found perfected in another, which Mr. Darwin
exemplifies by comparing the cells of the humble-bee,
the melipona domestica of Mexico, and the hive-bee,
ranging from great simplicity to an extreme perfection13?
But the principle of natural selection offers a solution
to every one of these enigmas. It embraces all the
various phases of life of the ancient world as well as the
modern, and gives a key to the whole grand uninterrupted
plan. It carries back the mind to a period when
the earth was destitute of life; when yet, as it were, the
thought in the Divine mind was still unspoken, that of
one, and that as good as dead, should spring seed like
the sand which is upon the sea-shore for multitude.
Then it came to pass that the dust of the earth was
called into life by the Life-Giver, and received the
strange command and the mysterious power to multiply,
and to replenish the earth. As soon as living creatures
multiplied to any great extent, they would spread themselves
into different lands and seas and climates; they
would find different sources of nourishment, and then
variation would come into play, and close upon variation
would follow selection, not of necessity destroying the
old forms, but establishing new ones, because in some
stations the form that had not varied might thrive best,
in others the variety would have an advantage14. As
time went on, through the constant changes that the
surface of the globe is undergoing, one variety would be
isolated from another, and in such an isolation the
differences would increase. And the more a species
varied, the more fitted it might become for some habitat,
from which it was completely cut off by a chain of
mountains, a rapid river, or a deep sea. As the competition
became more intense, variations would become
more and more valuable, enabling creatures to occupy
positions before untenable, ocean-depths, sandy shores,
holes in rocks, fresh-water lakes, tops of mountains,
branches of trees, the bodies of other living beings.
Some would be taught by necessity and enabled by
favourable variations to prey, as well as take up their
abode, on other creatures. And as the strife became
more and more urgent, all sorts of qualities that from
our point of view may seem noxious and degrading
might prove of the highest service and advantage to
their own possessors. Plants with sharp thorns and
envenomed hairs, poisonous snakes, trichinæ and other
parasites horrible to man, would find their advantage
at our cost, or by unparalleled fertility would defy all
efforts to extirpate them. Some species would profit by
minuteness, others by size; others, in various ways, by
talons, beak, thread-like tongue, prehensile tail, or furry
coat; and, just as men are said to go through fire and
water for the sake of money, so for the sake of preservation,
no habit, no locality would be too uncongenial for
a species to develope adaptation thereunto. And, accordingly,
we find that the water-ouzel, which is a species of
thrush, subsists entirely by diving; there is a tree-climbing
lobster in the Mauritius; there are fishes
which ramble about on the land, and one fish, the
anabas scandens, can climb eight or ten feet up the
trunk of a palm15.
The choice of food, the choice of habitation, the
construction of dwelling-places for themselves or their
offspring, methods of defence, methods of attack, are
variously carried out by myriads of species. The processes
employed, in man we call for the most part
rational; in the lower animals we call them instinctive;
but there are processes employed for these self-same
objects by vegetables as well as by men. For plants,
in one sense stationary, travel towards water by their
roots, towards light by their branches; they assimilate
the elements of nutriment that suit them, rejecting
others. The Sensitive plant shrinks from the touch,
Venus’s fly-trap closes round unwary insects and destroys
them. Tendrils fasten on the supports that are
offered them. Trees keep in their delicate blossoms
till the weather is genial. Many a corolla folds carefully
round stamens and pistils when the chilly twilight
approaches.
Pass from proceedings like these to the swimming
movements of a beheaded Dytiscus16, and other reflex
actions in animals, to the food-seeking movements of the
tentaculæ of the Hydra or fresh-water Polype, which
hover doubtfully between reflex and instinctive action:
go forward through the innumerable gradations of instinct
till you come, for instance, to the spider, weaving
its symmetrical web, rushing out of its lair to seize the
prey when the web is shaken lightly, but keeping itself
close from a too dangerous foe when the web is vehemently
shaken. Examine the nest of the Mygale (the
trap-door spider) lined with silken tapestry, furnished
with a door on a silken hinge, which it covers above
with materials like the surrounding soil, and holds from
beneath against an intruder, by applying its claws to
the most advantageous point, the point most distant
from the hinge: consider the little Sylvia Sutoria, or
tailor-bird, which draws filaments of cotton from the
cotton-plant, and sews leaves together with its beak
and feet to form a nest; go to the huts and river-dams
of the beaver; attend a conclave of rooks judging an
offender; look into the hive of the hive-bee; observe
the conscious vanity of the peacock; preach liberty to
the slave-making ants; watch the sagacious ways of
dogs and horses; and then lastly see if it be possible
to resist the conclusion that, were all forms that ever
existed, from the earliest geological times to our own,
present before us in the order of their genealogies, we
should see them to be the members of a single family,
now, indeed, immensely divergent, yet all united by
some affinity or affinities, whether dimly or conspicuously
shown.
How strangely men and beasts are united by similarity
of blood and fibre! How strangely fishes, birds,
and mammals by the likeness of the vertebrate skeleton!
How strangely plants and animals by the phenomena
of generation, not only in the union of the sexes, but
also in (agamogenesis) or asexual reproduction! Need
we wonder at community of origin between a coral and
a cactus, a whale and a sloth, a wolf and a Shylock,
when we find that a lady’s silken tresses, the bristles
of a boar, the quill of the porcupine, the feathers of
the owl, and the horns of the buffalo, are parallel and
specifically interchangeable developments?
Consider the vine, with its stem, branches, twigs,
roots, rootlets, leaves, tendrils, and the luscious grapes
of the ripe cluster. From one seed sprang all of these.
On the bough of an orange tree there live and grow
together leaf and petiole, flower and fruit, the green
unripe fruit, the yellow and the golden-ripe. All these
from one seed. Yet there is no jealousy among them.
No one disowns a kindred origin for the root of the
tree and its golden fruit, utterly unlike as these are,
but, like so many other utterly unlike things in this
world, sprung from the same germ.
To have produced and accumulated the vast divergences
that now exist, a lapse of time, indeed, must be
conceded, unmeasured and perhaps immeasurable; but
this lapse of time is precisely what geology, independently
of Darwinism, has already demanded. As the
Scriptures speak of the earth as immoveable, because
so it is in reference to the senses of man, they speak
also of the everlasting mountains, and with them the
rocks are a type of the eternal: compared with the
life of man these expressions are truthful and well-chosen,
but they do not mean to say the rocks are
as eternal as God, nor yet everlasting compared with
the existence of the globe. It may have taken ten
thousand centuries to rear up a mountain, and yet, if
we reckon the age of the globe on the scale of a man’s
life, the mountain be but of yesterday.
The immense antiquity, not only of the globe, but of
that thin crust of it open to our inspection, has been
ascertained by geology. Geology, again, has made it
certain that during millions of years, changes on the
earth’s surface have been in continual progress, so that
not once merely, but many times over, continents and
oceans must have yielded to one another, yet by no
sudden, but ever by a gradual transposition, such as is
in constant progress at the present day.
Seeing that the dwelling-place of living creatures
is thus continually and continuously changing, how
clumsy an arrangement it would have been had the
forms of life been made constant, instead of being
endowed, as they clearly have been, with a wonderful
power of adaptation. The question, be it remembered,
is not for a moment whether God has made the universe,
but how He has made that portion of it which
He has enabled us to see and examine. Nor yet, to
be thoroughly accurate, is it in question how He has
worked, but how He has been pleased to exhibit His
operations to the reasoning minds of men. What is
worthy of God we cannot indeed judge. We can only
believe that the things which are, stand worthiest of
His wisdom and goodness, whatever faults may seem
in them to our rashly-judging short-sightedness. But
comparing theories of creation according to human
notions, is it a nobler conception that God should
have made successively groups of beings to fill the
world, and then swept them away to make room for
others nearly like them; each time, as it were, improving
on His first idea, and so arguing the imperfection
of what had gone before by the very improvement
of what followed; or that, foreseeing the perfect
types from the beginning, He should have called into
existence seeds of life capable, under the laws He gave
them, of rising in successive generations through countless
ages, to endowments of the noblest order, to a
conscious life, to a reasoning faculty, to a moral sense,
to a knowledge of God? In such an origin there is
for man no degradation, since the lowliness of his
parentage has ever been traced back to the dust of
the ground; and the lowest form of life is higher in
our imaginations than the dull brute earth. Indeed,
if we desire to exalt our self-appreciation, whether is
it grander for us to have been the work of an instant,
or to have been elaborated with Divine care through
millions of ages? Will not any miracle in our behalf,
however stupendous, seem more credible on the latter
than on the former supposition? When we see what
Development has already done for the human species,
we can the more readily imagine what, under the same
Lawgiver, it may do in the future for the individuals
of our race. When we find it possible or probable
that our own bodies contain resemblances to ancestors
enormously remote in time, simply because they contain
atoms from the bodies of those very ancestors
living again in ourselves, we can understand how in
a future, whether near or enormously remote, atoms
from the very body of the man that dies may be
called into a renewed existence, and clothed again with
all that is necessary to personal identity, though haply
more transformed and higher raised above the old self,
than would be an orang-outang or a naked savage,
were either of these enabled to combine the chivalric
courtesy of Sir Philip Sydney with the genius of
Sophocles and Shakespeare.