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I have entitled this volume "Darwiniana"because the pieces republished in it eithertreat of the ancient doctrine of Evolution,rehabilitated and placed upon a soundscientific foundation,

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Darwiniana, by Thomas Henry Huxley

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Thomas Henry Huxley

Collected Essays

(1893-1894)

Vol II

Darwiniana

(Edition: published in 1893)

I have entitled this volume "Darwiniana"because the pieces republished in it eithertreat of the ancient doctrine of Evolution,rehabilitated and placed upon a soundscientific foundation, since and in

consequence of, the publication of the

"Origin of Species;" or they attempt tomeet the more weighty of the unsparingcriticisms with which that great work wasvisited for several years after its

appearance; or they record the impressionleft by the personality of Mr Darwin onone who had the privilege and the

happiness of enjoying his friendship for

some thirty years; or they endeavour tosum up his work and indicate its enduringinfluence on the course of scientific

up in these two essays; and the assertionwhich I sometimes meet with nowadays,that I have "recanted" or changed myopinions about Mr Darwin's views, is

quite unintelligible to me.

As I have said in the seventh essay, thefact of evolution is to my mind sufficientlyevidenced by palaeontology; and I remain

of the opinion expressed in the second,that until selective breeding is definitelyproved to give rise to varieties infertilewith one another, the logical foundation ofthe theory of natural selection is

incomplete We still remain very much inthe dark about the causes of variation; theapparent inheritance of acquired

characters in some cases; and the strugglefor existence within the organism, whichprobably lies at the bottom of both ofthese phenomena

Some apology is due to the reader for the

reproduction of the "Lectures to WorkingMen" in their original state They weretaken down in shorthand by Mr J AldousMays, who requested me to allow him toprint them I was very much pressed withwork at the time; and, as I could not revisethe reports, which I imagined, moreover,would be of little or no interest to any but

my auditors, I stipulated that a noticeshould be prefixed to that effect This wasdone; but it did not prevent a considerablediffusion of the little book in this countryand in the United States, nor its translationinto more than one foreign language

Moreover Mr Darwin often urged me torevise and expand the lectures into a

systematic popular exposition of the

topics of which they treat I have morethan once set about the task: but the

proverb about spoiling a horn and notmaking a spoon, is particularly applicable

to attempts to remodel a piece of workwhich may have served its immediatepurpose well enough

So I have reprinted the lectures as theystand, with all their imperfections on theirheads It would seem that many peoplemust have found them useful thirty yearsago; and, though the sixties appear now to

be reckoned by many of the rising

generation as a part of the dark ages, I amnot without some grounds for suspectingthat there yet remains a fair sprinklingeven of "philosophic thinkers" to whom itmay be a profitable, perhaps even a novel,task to descend from the heights of

speculation and go over the A B C of the

great biological problem as it was setbefore a body of shrewd artisans at thatremote epoch.

T H H.

Hodeslea, Eastbourne, April 7th, 1893.

I THE DARWINIAN HYPOTHESIS [1859]

II THE ORIGIN OF SPECIES [1860]

III CRITICISM ON "THE ORIGIN OF SPECIES" [1864]

IV THE GENEALOGY OF ANIMALS [1869]

V MR DARWIN'S CRITICS [1871]

VI EVOLUTION IN BIOLOGY [1878]

VII THE COMING OF AGE OF "THE ORIGIN OF SPECIES" [1880]

VIII CHARLES DARWIN [1882]

IX THE DARWIN MEMORIAL [1885]

X OBITUARY [1888]

XI SIX LECTURES TO WORKING MEN

"ON OUR KNOWLEDGE OF THE CAUSES

OF THE PHENOMENA OF ORGANIC NATURE" [1863]

THE DARWINIAN HYPOTHESIS

[1859]

The hypothesis of which the present work

of Mr Darwin is but the preliminaryoutline, may be stated in his own language

as follows:— "Species originated bymeans of natural selection, or through thepreservation of the favoured races in thestruggle for life." To render this thesisintelligible, it is necessary to interpret itsterms In the first place, what is a species?The question is a simple one, but the right

answer to it is hard to find, even if weappeal to those who should know mostabout it It is all those animals or plantswhich have descended from a single pair

of parents; it is the smallest distinctlydefinable group of living organisms; it is

an eternal and immutable entity; it is amere abstraction of the human intellecthaving no existence in nature Such are afew of the significations attached to thissimple word which may be culled fromauthoritative sources; and if, leaving termsand theoretical subtleties aside, we turn tofacts and endeavour to gather a meaningfor ourselves, by studying the things towhich, in practice, the name of species isapplied, it profits us little For practicevaries as much as theory Let two

botanists or two zoologists examine and

describe the productions of a country, andone will pretty certainly disagree with theother as to the number, limits, and

definitions of the species into which hegroups the very same things In theseislands, we are in the habit of regardingmankind as of one species, but a

fortnight's steam will land us in a countrywhere divines and savants, for once inagreement, vie with one another in

loudness of assertion, if not in cogency ofproof, that men are of different species;and, more particularly, that the speciesnegro is so distinct from our own that theTen Commandments have actually noreference to him Even in the calm region

of entomology, where, if anywhere in thissinful world, passion and prejudice

should fail to stir the mind, one learned

coleopterist will fill ten attractive

volumes with descriptions of species ofbeetles, nine-tenths of which are

immediately declared by his brother

beetle-mongers to be no species at all

The truth is that the number of

distinguishable living creatures almostsurpasses imagination At least 100,000such kinds of insects alone have beendescribed and may be identified in

collections, and the number of separablekinds of living things is under-estimated athalf a million Seeing that most of theseobvious kinds have their accidental

varieties, and that they often shade intoothers by imperceptible degrees, it maywell be imagined that the task of

distinguishing between what is permanent

and what fleeting, what is a species andwhat a mere variety, is sufficiently

formidable

But is it not possible to apply a test

whereby a true species may be knownfrom a mere variety? Is there no criterion

of species? Great authorities affirm thatthere is—that the unions of members of thesame species are always fertile, whilethose of distinct species are either sterile,

or their offspring, called hybrids, are so It

is affirmed not only that this is an

experimental fact, but that it is a provisionfor the preservation of the purity of

species Such a criterion as this would beinvaluable; but, unfortunately, not only is

it not obvious how to apply it in the greatmajority of cases in which its aid is

needed, but its general validity is stoutlydenied The Hon and Rev Mr Herbert, amost trustworthy authority, not only

asserts as the result of his own

observations and experiments that manyhybrids are quite as fertile as the parentspecies, but he goes so far as to assert that

the particular plant Crinum capense is

much more fertile when crossed by adistinct species than when fertilised by itsproper pollen! On the other hand, thefamous Gaertner, though he took the

greatest pains to cross the Primrose andthe Cowslip, succeeded only once ortwice in several years; and yet it is awell-established fact that the Primroseand the Cowslip are only varieties of thesame kind of plant Again, such cases asthe following are well established The

female of species A, if crossed with themale of species B, is fertile; but, if thefemale of B is crossed with the male of A,she remains barren Facts of this kinddestroy the value of the supposed

criterion

If, weary of the endless difficulties

involved in the determination of species,the investigator, contenting himself withthe rough practical distinction of

separable kinds, endeavours to study them

as they occur in nature—to ascertain theirrelations to the conditions which surroundthem, their mutual harmonies and

discordancies of structure, the bond ofunion of their present and their past

history, he finds himself, according to thereceived notions, in a mighty maze, and

with, at most, the dimmest adumbration of

a plan If he starts with any one clearconviction, it is that every part of a livingcreature is cunningly adapted to somespecial use in its life Has not his Paleytold him that that seemingly useless organ,the spleen, is beautifully adjusted as somuch packing between the other organs?And yet, at the outset of his studies, hefinds that no adaptive reason whatsoevercan be given for one-half of the

peculiarities of vegetable structure Healso discovers rudimentary teeth, whichare never used, in the gums of the youngcalf and in those of the foetal whale;insects which never bite have rudimentaljaws, and others which never fly haverudimental wings; naturally blind

creatures have rudimental eyes; and the

halt have rudimentary limbs So, again, noanimal or plant puts on its perfect form atonce, but all have to start from the samepoint, however various the course whicheach has to pursue Not only men andhorses, and cats and dogs, lobsters andbeetles, periwinkles and mussels, but eventhe very sponges and animalcules

commence their existence under formswhich are essentially undistinguishable;and this is true of all the infinite variety ofplants Nay, more, all living beings march,side by side, along the high road of

development, and separate the later themore like they are; like people leavingchurch, who all go down the aisle, buthaving reached the door, some turn intothe parsonage, others go down the village,and others part only in the next parish A

man in his development runs for a littlewhile parallel with, though never passingthrough, the form of the meanest worm,then travels for a space beside the fish,then journeys along with the bird and thereptile for his fellow travellers: and only

at last, after a brief companionship withthe highest of the four-footed and four-handed world, rises into the dignity ofpure manhood No competent thinker ofthe present day dreams of explaining theseindubitable facts by the notion of theexistence of unknown and undiscoverableadaptations to purpose And we wouldremind those who, ignorant of the facts,must be moved by authority, that no onehas asserted the incompetence of thedoctrine of final causes, in its application

to physiology and anatomy, more strongly

than our own eminent anatomist, ProfessorOwen, who, speaking of such cases, says("On the Nature of Limbs," pp 39, 40)

—"I think it will be obvious that the

principle of final adaptations fails tosatisfy all the conditions of the problem."

But, if the doctrine of final causes will nothelp us to comprehend the anomalies ofliving structure, the principle of

adaptation must surely lead us to

understand why certain living beings arefound in certain regions of the world andnot in others The Palm, as we know, willnot grow in our climate, nor the Oak inGreenland The white bear cannot live

where the tiger thrives, nor vice versâ,

and the more the natural habits of animaland vegetable species are examined, the

more do they seem, on the whole, limited

to particular provinces But when we lookinto the facts established by the study ofthe geographical distribution of animalsand plants it seems utterly hopeless toattempt to understand the strange and

apparently capricious relations which theyexhibit One would be inclined to suppose

à priori that every country must be

naturally peopled by those animals thatare fittest to live and thrive in it And yethow, on this hypothesis, are we to accountfor the absence of cattle in the Pampas ofSouth America, when those parts of theNew World were discovered? It is notthat they were unfit for cattle, for millions

of cattle now run wild there; and the likeholds good of Australia and New Zealand

It is a curious circumstance, in fact, that

the animals and plants of the NorthernHemisphere are not only as well adapted

to live in the Southern Hemisphere as itsown autochthones, but are, in many cases,absolutely better adapted, and so overrunand extirpate the aborigines Clearly,therefore, the species which naturallyinhabit a country are not necessarily thebest adapted to its climate and other

conditions The inhabitants of islands areoften distinct from any other known

species of animal or plants (witness ourrecent examples from the work of SirEmerson Tennent, on Ceylon), and yet theyhave almost always a sort of general

family resemblance to the animals andplants of the nearest mainland On theother hand, there is hardly a species offish, shell, or crab common to the opposite

sides of the narrow isthmus of Panama.

[Footnote: See page 60 Note.] Wherever

we look, then, living nature offers usriddles of difficult solution, if we supposethat what we see is all that can be known

of it

But our knowledge of life is not confined

to the existing world Whatever theirminor differences, geologists are agreed

as to the vast thickness of the accumulatedstrata which compose the visible part ofour earth, and the inconceivable

immensity of the time the lapse of whichthey are the imperfect but the only

accessible witnesses Now, throughout thegreater part of this long series of stratifiedrocks are scattered, sometimes very

abundantly, multitudes of organic remains,

the fossilised exuviæ of animals and

plants which lived and died while the mud

of which the rocks are formed was yet softooze, and could receive and bury them Itwould be a great error to suppose thatthese organic remains were fragmentaryrelics Our museums exhibit fossil shells

of immeasurable antiquity, as perfect asthe day they were formed; whole skeletonswithout a limb disturbed; nay, the changedflesh, the developing embryos, and eventhe very footsteps of primæval organisms.Thus the naturalist finds in the bowels ofthe earth species as well defined as, and

in some groups of animals more numerousthan, those which breathe the upper air.But, singularly enough, the majority ofthese entombed species are wholly

distinct from those that now live Nor is

this unlikeness without its rule and order.

As a broad fact, the further we go back intime the less the buried species are likeexisting forms; and, the further apart thesets of extinct creatures are, the less theyare like one another In other words, therehas been a regular succession of livingbeings, each younger set, being in a verybroad and general sense, somewhat morelike those which now live

It was once supposed that this successionhad been the result of vast successivecatastrophes, destructions, and re-

creations en masse; but catastrophes are

now almost eliminated from geological, or

at least palæontological speculation; and

it is admitted, on all hands, that the

seeming breaks in the chain of being are

not absolute, but only relative to our

imperfect knowledge; that species havereplaced species, not in assemblages, butone by one; and that, if it were possible tohave all the phenomena of the past

presented to us, the convenient epochs andformations of the geologist, though having

a certain distinctness, would fade into oneanother with limits as undefinable as those

of the distinct and yet separable colours ofthe solar spectrum

Such is a brief summary of the main truthswhich have been established concerningspecies Are these truths ultimate andirresolvable facts, or are their

complexities and perplexities the mereexpressions of a higher law?

A large number of persons practicallyassume the former position to be correct.They believe that the writer of the

Pentateuch was empowered and

commissioned to teach us scientific aswell as other truth, that the account wefind there of the creation of living things issimply and literally correct, and that

anything which seems to contradict it is,

by the nature of the case, false All thephenomena which have been detailed are,

on this view, the immediate product of acreative fiat and, consequently, are out ofthe domain of science altogether

Whether this view prove ultimately to betrue or false, it is, at any rate, not at

present supported by what is commonlyregarded as logical proof, even if it be

capable of discussion by reason; andhence we consider ourselves at liberty topass it by, and to turn to those views

which profess to rest on a scientific basisonly, and therefore admit of being argued

to their consequences And we do thiswith the less hesitation as it so happensthat those persons who are practicallyconversant with the facts of the case

(plainly a considerable advantage) havealways thought fit to range themselvesunder the latter category

The majority of these competent personshave up to the present time maintained twopositions—the first, that every species is,within certain defined limits, fixed andincapable of modification; the second, thatevery species was originally produced by

a distinct creative act The second

position is obviously incapable of proof

or disproof, the direct operations of theCreator not being subjects of science; and

it must therefore be regarded as a

corollary from the first, the truth or

falsehood of which is a matter of

evidence Most persons imagine that thearguments in favour of it are

overwhelming; but to some few minds,and these, it must be confessed, intellects

of no small power and grasp of

knowledge, they have not brought

conviction Among these minds, that of thefamous naturalist Lamarck, who possessed

a greater acquaintance with the lowerforms of life than any man of his day,Cuvier not excepted, and was a goodbotanist to boot, occupies a prominent

Two facts appear to have strongly affectedthe course of thought of this remarkableman—the one, that finer or stronger links

of affinity connect all living beings withone another, and that thus the highest

creature grades by multitudinous steps intothe lowest; the other, that an organ may bedeveloped in particular directions byexerting itself in particular ways, and thatmodifications once induced may be

transmitted and become hereditary Puttingthese facts together, Lamarck endeavoured

to account for the first by the operation ofthe second Place an animal in new

circumstances, says he, and its needs will

be altered; the new needs will create newdesires, and the attempt to gratify such

desires will result in an appropriate

modification of the organs exerted Make

a man a blacksmith, and his brachial

muscles will develop in accordance withthe demands made upon them, and in likemanner, says Lamarck, "the efforts ofsome short-necked bird to catch fish

without wetting himself have, with timeand perseverance, given rise to all ourherons and long-necked waders."

The Lamarckian hypothesis has long sincebeen justly condemned, and it is the

established practice for every tyro to raisehis heel against the carcase of the deadlion But it is rarely either wise or

instructive to treat even the errors of areally great man with mere ridicule, and inthe present case the logical form of the

doctrine stands on a very different footingfrom its substance.

If species have really arisen by the

operation of natural conditions, we ought

to be able to find those conditions now atwork; we ought to be able to discover innature some power adequate to modifyany given kind of animal or plant in such amanner as to give rise to another kind,which would be admitted by naturalists as

a distinct species Lamarck imagined that

he had discovered this vera causa in the

admitted facts that some organs may bemodified by exercise; and that

modifications, once produced, are capable

of hereditary transmission It does notseem to have occurred to him to inquirewhether there is any reason to believe that

there are any limits to the amount ofmodification producible, or to ask howlong an animal is likely to endeavour togratify an impossible desire The bird, inour example, would surely have

renounced fish dinners long before it hadproduced the least effect on leg or neck

Since Lamarck's time, almost all

competent naturalists have left

speculations on the origin of species tosuch dreamers as the author of the

"Vestiges," by whose well-intentionedefforts the Lamarckian theory received itsfinal condemnation in the minds of allsound thinkers Notwithstanding thissilence, however, the transmutation

theory, as it has been called, has been a

"skeleton in the closet" to many an honest

zoologist and botanist who had a soulabove the mere naming of dried plants andskins Surely, has such an one thought,nature is a mighty and consistent whole,and the providential order established inthe world of life must, if we could onlysee it rightly, be consistent with that

dominant over the multiform shapes ofbrute matter But what is the history ofastronomy, of all the branches of physics,

of chemistry, of medicine, but a narration

of the steps by which the human mind hasbeen compelled, often sorely against itswill, to recognise the operation of

secondary causes in events where

ignorance beheld an immediate

intervention of a higher power? And when

we know that living things are formed ofthe same elements as the inorganic world,

that they act and react upon it, bound by athousand ties of natural piety, is it

probable, nay is it possible, that they, andthey alone, should have no order in theirseeming disorder, no unity in their

seeming multiplicity, should suffer noexplanation by the discovery of somecentral and sublime law of mutual

connection?

Questions of this kind have assuredlyoften arisen, but it might have been longbefore they received such expression aswould have commanded the respect andattention of the scientific world, had it notbeen for the publication of the work whichprompted this article Its author, Mr

Darwin, inheritor of a once celebratedname, won his spurs in science when most