Lamarck, the Founder of Evolution

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The Buffonian factor of the direct influence of climate is not in
general of so thoroughgoing a character as usually supposed by the
commentators of Buffon. He generally applies it to the superficial
changes, such as the increase or decrease in the amount of hair, or
similar modifications not usually regarded as specific characters. The
modifications due to the direct influence of climate may be effected, he
says, within even a few generations.

Under the head of geographical distribution (in tome ix., 1761), in
which subject Buffon made his most original contribution to exact
biology, he claims to have been the first "even to have suspected" that
not a single tropical species is common to both eastern and western
continents, but that the animals common to both continents are those
adapted to a temperate or cold climate. He even anticipates the subject
of migration in past geological times by supposing that those forms
travelled from the Old World either over some land still unknown, or
"more probably" over territory which has long since been submerged.[135]

The mammoth "was certainly the greatest and strongest of all
quadrupeds, but it has disappeared; and if so, how many smaller,
feebler, and less remarkable species must have perished without
leaving us any traces or even hints of their having existed? How
many other species have changed their nature, that is to say,
become perfected or degraded, through great changes in the
distribution of land and ocean; through the cultivation or neglect
of the country which they inhabit; through the long-continued
effects of climatic changes, so that they are no longer the same
animals that they once were. Yet of all living beings after man the
quadrupeds are the ones whose nature is most fixed and form most
constant; birds and fishes vary much more easily; insects still more
again than these; and if we descend to plants, which certainly
cannot be excluded from animated nature, we shall be surprised at
the readiness with which species are seen to vary, and at the ease
with which they change their forms and adopt new natures."[136]

The following passages, debarring the error of deriving all the American
from the Old World forms, and the mistake in supposing that the American
forms grew smaller than their ancestors in the Old World, certainly
smack of the principle of isolation and segregation, and this is
Buffon's most important contribution to the theory of descent.

"It is probable, then, that all the animals of the New World are
derived from congeners in the Old, without any deviation from the
ordinary course of nature. We may believe that, having become
separated in the lapse of ages by vast oceans and countries which
they could not traverse, they have gradually been affected by, and
derived impressions from, a climate which has itself been modified
so as to become a new one through the operations of those same
causes which dissociated the individuals of the Old and the New
World from one another; thus in the course of time they have grown
smaller and changed their characters. This, however, should not
prevent our classifying them as different species now, for the
difference is no less real though it dates from the creation.
_Nature, I maintain, is in a state of continual flux and movement.
It is enough for man if he can grasp her as she is in his own time,
and throw but a glance or two upon the past and future, so as to try
and perceive what she may have been in former times and what one day
she may attain to._"[137]

Buffon thus suggests the principle of the struggle for existence to
prevent overcrowding, resulting in the maintenance of the balance of
nature:

"It may be said that the movement of Nature turns upon two immovable
pivots--one, the illimitable fecundity which she has given to all
species; the other, the innumerable difficulties which reduce the
results of that fecundity, and leave throughout time nearly the same
quantity of individuals in every species; ... destruction and
sterility follow closely upon excessive fecundity, and,
independently of the contagion which follows inevitably upon
overcrowding, each species has its own special sources of death and
destruction, which are of themselves sufficient to compensate for
excess in any past generation."[138]

He also adds, "The species the least perfect, the most delicate, the
most unwieldy, the least active, the most unarmed, etc., have already
disappeared or will disappear."[139]

On one occasion, in writing on the dog, he anticipates Erasmus Darwin
and Lamarck in ascribing to the direct cause of modification the inner
feelings of the animal modified, change of condition being the indirect
cause.[140] He, however, did not suggest the idea of the transmission of
acquired characters by heredity, and does not mention the word heredity.

These are all the facts he stated; but though not an observer, Buffon
was a broad thinker, and was led from these few data to generalize, as
he could well do, from the breadth of his knowledge of geology gained
from the works of his predecessors, from Leibnitz to Woodward and
Whiston.

"After the rapid glance," he says, "at these variations, which
indicate to us the special changes undergone by each species, there
arises a more important consideration, and the view of which is
broader; it is that of the transformation (_changement_) of the
species themselves; it is that more ancient modification which has
gone on from time immemorial, which seems to have been made in each
family or, if we prefer, in each of the genera in which were
comprised more or less allied species."[141]

In the beginning of his first volume he states "that we can descend by
almost imperceptible degrees from the most perfect creature to the most
formless matter--from the most highly organized animal to the most
entirely inorganic substance. We will recognize this gradation as the
great work of nature; and we will observe it not only as regards size
and form, but also in respect of movements and in the successive
generations of every species."

"Hence," he continues, "arises the difficulty of arriving at any
perfect system or method in dealing either with nature as a whole or
even with any single one of her subdivisions. The gradations are so
subtle that we are often obliged to make arbitrary divisions. Nature
knows nothing about our classifications, and does not choose to lend
herself to them without reasons. We therefore see a number of
intermediate species and objects which it is very hard to classify,
and which of necessity derange our system, whatever it may be."[142]

This is all true, and was probably felt by Buffon's predecessors, but it
does not imply that he thought these forms had descended from one
another.

"In thus comparing," he adds, "all the animals, and placing them
each in its proper genus, we shall find that the two hundred species
whose history we have given may be reduced to a quite small number
of families or principal sources from which it is not impossible
that all the others may have issued."[143]

He then establishes, on the one hand, nine species which he regarded as
isolated, and, on the other, fifteen principal genera, primitive sources
or, as we would say, ancestral forms, from which he derived all the
animals (mammals) known to him.

Hence he believed that he could derive the dog, the jackal, the wolf,
and the fox from a single one of these four species; yet he remarks,
_per contra_, in 1753:

"Although we cannot demonstrate that the production of a species by
modification is a thing impossible to nature, the number of
contrary probabilities is so enormous that, even philosophically, we
can scarcely doubt it; for if any species has been produced by the
modification of another, if the species of ass has been derived from
that of the horse, this could have been done only successively and
by gradual steps: there would have been between the horse and ass a
great number of intermediate animals, the first of which would
gradually differ from the nature of the horse, and the last would
gradually approach that of the ass; and why do we not see to-day the
representatives, the descendants of those intermediate species? Why
are only the two extremes living?" (tome iv., p. 390). "If we once
admit that the ass belongs to the horse family, and that it only
differs from it because it has been modified (_degenere_), we may
likewise say that the monkey is of the same family as man, that it
is a modified man, that man and the monkey have had a common origin
like the horse and ass, that each family has had but a single
source, and even that all the animals have come from a single
animal, which in the succession of ages has produced, while
perfecting and modifying itself, all the races of other animals"
(tome iv., p. 382). "If it were known that in the animals there had
been, I do not say several species, but a single one which had been
produced by modification from another species; if it were true that
the ass is only a modified horse, there would be no limit to the
power of nature, and we would not be wrong in supposing that from a
single being she has known how to derive, with time, all the other
organized beings" (_ibid._, p. 382).

The next sentence, however, translated, reads as follows:

"But no. It is certain from revelation that all animals have alike
been favored with the grace of an act of direct creation, and that
the first pair of every species issued fully formed from the hands
of the Creator" (tome iv., p. 383).

In which of these views did Buffon really believe? Yet they appear in
the same volume, and not at different periods of his life.

He actually does say in the same volume (iv., p. 358): "It is not
impossible that all species may be derivations (_issues_)." In the same
volume also (p. 215) he remarks:

"There is in nature a general prototype in each species on which
each individual is modelled, but which seems, in being realized, to
change or become perfected by circumstances; so that, relatively to
certain qualities, there is a singular (_bizarre_) variation in
appearance in the succession of individuals, and at the same time a
constancy in the entire species which appears to be admirable."

And yet we find him saying at the same period of his life, in the
previous volume, that species "are the only beings in nature, beings
perpetual, as ancient, as permanent as she."[144] A few pages farther on
in the same volume of the same work, apparently written at the same
time, he is strongly and stoutly anti-evolutional, affirming: "The
imprint of each species is a type whose principal features are graven in
characters forever ineffaceable and permanent."[145]

In this volume (iv., p. 55) he remarks that the senses, whether in man
or in animals, may be greatly developed by exercise.

The impression left on the mind, after reading Buffon, is that even if
he threw out these suggestions and then retracted them, from fear of
annoyance or even persecution from the bigots of his time, he did not
himself always take them seriously, but rather jotted them down as
passing thoughts. Certainly he did not present them in the formal,
forcible, and scientific way that Erasmus Darwin did. The result is that
the tentative views of Buffon, which have to be with much research
extracted from the forty-four volumes of his works, would now be
regarded as in a degree superficial and valueless. But they appeared
thirty-four years before Lamarck's theory, and though not epoch-making,
they are such as will render the name of Buffon memorable for all time.

ETIENNE GEOFFROY ST. HILAIRE.

Etienne Geoffroy St. Hilaire was born at Etampes, April 15, 1772. He
died in Paris in 1844. He was destined for the church, but his tastes
were for a scientific career. His acquaintance with the Abbe Hauey and
Daubenton led him to study mineralogy. He was the means of liberating
Hauey from a political prison; the Abbe, as the result of the events of
August, 1792, being promptly set free at the request of the Academy of
Sciences. The young Geoffroy was in his turn aided by the illustrious
Hauey, who obtained for him the position of sub-guardian and demonstrator
of mineralogy in the Cabinet of Natural History. At the early age of
twenty-one years, as we have seen, he was elected professor of zooelogy
in the museum, in charge of the department of mammals and birds. He was
the means of securing for Cuvier, then of his own age, a position in the
museum as professor-adjunct of comparative anatomy. For two years (1795
and 1796) the two youthful savants were inseparable, sharing the same
apartments, the same table, the same amusements, the same studies, and
their scientific papers were prepared in company and signed in common.

[Illustration: E. GEOFFROY ST. HILAIRE]

Geoffroy became a member of the great scientific commission sent to
Egypt by Napoleon (1789-1802). By his boldness and presence of mind he,
with Savigny and the botanist Delille, saved the treasures which at
Alexandria had fallen into the hands of the English general in command.
In 1808 he was charged by Napoleon with the duty of organizing public
instruction in Portugal. Here again, by his address and firmness, he
saved the collections and exchanges made there from the hands of the
English. When thirty-six years old he was elected a member of the
Institute.

In 1818 he began to discuss philosophical anatomy, the doctrine of
homologies; he also studied the embryology of the mammals, and was the
founder of teratology. It was he who discovered the vestigial teeth of
the baleen whale and those of embryo birds, and the bearing of this on
the doctrine of descent must have been obvious to him.

As early as 1795, before Lamarck had changed his views as to the
stability of species, the young Geoffroy, then twenty-three years old,
dared to claim that species may be only "_les diverses degenerations
d'un meme type_." These views he did not abandon, nor, on the other
hand, did he actively promulgate them. It was not until thirty years
later, in his memoir on the anatomy of the gavials, that he began the
series of his works bearing on the question of species. In 1831 was held
the famous debates between himself and Cuvier in the Academy of
Sciences. But the contest was not so much on the causes of the variation
of species as on the doctrine of homologies and the unity of
organization in the animal kingdom.

In fact, Geoffroy did not adopt the views peculiar to his old friend
Lamarck, but was rather a follower of Buffon. His views were preceded by
two premises.

The species is only "_fixe sous la raison du maintien de l'etat
conditionnel de son milieu ambiant_."

It is modified, it changes, if the environment (_milieu ambiant_)
varies, and according to the extent (selon la portee) of the variations
of the latter.[146]

As the result, among recent or living beings there are no essential
differences as regards them--"_c'est le meme cours d'evenements_," or
"_la meme marche d'excitation_."[147]

On the other hand, the _monde ambiant_ having undergone more or less
considerable change from one geological epoch to another, the atmosphere
having even varied in its chemical composition, and the conditions of
respiration having been thus modified,[148] the beings then living would
differ in structure from their ancestors of ancient times, and would
differ from them according "to the degree of the modifying power."[149]
Again, he says, "The animals living to-day have been derived by a series
of uninterrupted generations from the extinct animals of the
antediluvian world."[150] He gave as an example the crocodiles of the
present day, which he believed to have descended from the fossil forms.
While he admitted the possibility of one type passing into another,
separated by characters of more than generic value, he always, according
to his son Isidore, rejected the view which made all the living species
descend "_d'une espece antediluvienne primitive_."[151] It will be seen
that Geoffroy St. Hilaire's views were chiefly based on palaeontological
evidence. He was throughout broad and philosophical, and his eloquent
demonstration in his _Philosophie anatomique_ of the doctrine of
homologies served to prepare the way for modern morphology, and affords
one of the foundation stones on which rests the theory of descent.
Though temporarily vanquished in the debate with Cuvier, who was a
forceful debater and represented the views then prevalent, a later
generation acknowledges that he was in the right, and remembers him as
one of the founders of evolution.

FOOTNOTES:

[125] Mr. Morley, in his _Rousseau_, gives a startling picture of the
hostility of the parliament at the period (1762) when Buffon's works
appeared. Not only was Rousseau hunted out of France, and his books
burnt by the public executioner, but there was "hardly a single man of
letters of that time who escaped arbitrary imprisonment" (p. 270); among
others thus imprisoned was Diderot. At this time (1750-1765) Malesherbes
(born 1721, guillotined 1794), one of the "best instructed and most
enlightened men of the century," was Directeur de la Libraire. "The
process was this: a book was submitted to him; he named a censor for it;
on the censor's report the director gave or refused permission to print
or required alterations. Even after these formalities were complied
with, the book was liable to a decree of the royal council, a decree of
the parliament, or else a lettre-de-cachet might send the author to the
Bastille" (Morley's _Rousseau_, p. 266).

[126] _Histoire naturelle, generale et particuliere._ 1st edition.
Imprimerie royale. Paris: 1749-1804, 44 vols. 4to. Tome iv., p. 357.
This is the best of all the editions of Buffon, says Flourens, from
whose _Histoire des Travaux et des Idees de Buffon_, 1st edition (Paris,
1844), we take some of the quotations and references, which, however, we
have verified. We have also quoted some passages from Buffon translated
by Butler in his "Evolution, Old and New" (London, 1879).

[127] _L. c._, tome iv., p. 384 (1753). This is the first volume on the
animals below man.

[128] Tome xi., p. 369 (1764).

[129] Tome xii., p. 3 (1764).

[130] Tome v., p. 59 (1755).

[131] Tome xiii., p. vii. (1765).

[132] Osborn adopts, without warrant we think, Isidore Geoffroy
St. Hilaire's notion, stating that he "shows clearly that his opinions
marked three periods." The writings of Isidore, the son of Etienne
Geoffroy, have not the vigor, exactness, or depth of those of his
father.

[133] Tome xiv., p. 326 (1766).

[134] Tome vi., pp. 59-60 (1756).

[135] Butler, _l. c._, pp. 145-146.

[136] Tome ix., p. 127, 1761 (_ex_ Butler).

[137] Tome ix., p. 127, 1761 (_ex_ Butler).

[138] Tome vi., p. 252, 1756 (quoted from Butler, _l. c._, pp. 123-126).

[139] Quoted from Osborn, who takes it from De Lanessan.

[140] Butler, _l. c._, p. 122 (from Buffon, tome v., 1755).

[141] Tome xiv., p. 335 (1766).

[142] Tome i., p. 13.

[143] Tome xiv., p. 358.

[144] Tome xiii., p. i.

[145] Tome xiii., p. ix.

[146] _Etudes progressives d'un Naturaliste_, etc., 1835, p. 107.

[147] _Ibid._

[148] _Sur l'Influence du Monde ambiant pour modifier les Formes animaux
(Memoires Acad. Sciences_, xii., 1833, pp. 63, 75).

[149] _Recherches sur l'Organisation des Gavials (Memoires du Museum
d'Histoire naturelle_), xii., p. 97 (1825).

[150] _Sur l'Influence du Monde ambiant_, p. 74.

[151] _Dictionnaire de la Conversation_, xxxi., p. 487, 1836 (quoted by
I. Geoffroy St. Hilaire); _Histoire nat. gen. des Regnes organiques_,
ii., 2^e partie; also _Resume_, p. 30 (1859).

CHAPTER XIV

THE VIEWS OF ERASMUS DARWIN

Erasmus Darwin, the grandfather of Charles Darwin, was born in 1731, or
twenty-four years after Buffon. He was an English country physician with
a large practice, and not only interested in philosophy, mechanics, and
natural science, but given to didactic rhyming, as evinced by _The
Botanical Garden_ and _The Loves of the Plants_, the latter of which was
translated into French in 1800, and into Italian in 1805. His "shrewd
and homely mind," his powers of keen observation and strong common sense
were revealed in his celebrated work _Zoonomia_, which was published in
two volumes in 1794, and translated into German in 1795-99. He was not a
zooelogist, published no separate scientific articles, and his striking
and original views on evolution, which were so far in advance of his
time, appear mostly in the section on "Generation," comprising 173 pages
of his _Zoonomia_,[152] which was mainly a medical work. The book was
widely read, excited much discussion, and his views decided opposition.
Samuel Butler in his _Evolution, Old and New_ (1879) remarks: "Paley's
_Natural Theology_ is written throughout at the _Zoonomia_, though he
is careful, _moro suo_, never to mention this work by name. Paley's
success was probably one of the chief causes of the neglect into which
the Buffonian and Darwinian systems fell in this country." Dr. Darwin
died in the same year (1802) as that in which the _Natural Theology_ was
published.

Krause also writes of the reception given by his contemporaries to his
"physio-philosophical ideas." "They spoke of his wild and eccentric
fancies, and the expression 'Darwinising' (as employed, for example, by
the poet Coleridge when writing on Stillingfleet) was accepted in
England nearly as the antithesis of sober biological investigation."[153]

The grandson of Erasmus Darwin had little appreciation of the views of
him of whom, through atavic heredity, he was the intellectual and
scientific child. "It is curious," he says in the 'Historical Sketch' of
the _Origin of Species_--"it is curious how largely my grandfather,
Dr. Erasmus Darwin, anticipated the views and erroneous grounds of
opinion of Lamarck in his _Zoonomia_ (vol. i., pp. 500-510), published
in 1794." It seems a little strange that Charles Darwin did not devote a
few lines to stating just what his ancestor's views were, for certain of
them, as we shall see, are anticipations of his own.

The views of Erasmus Darwin may thus be summarily stated:

1. All animals have originated "from a single living filament" (p. 230),
or, stated in other words, referring to the warm-blooded animals alone,
"one is led to conclude that they have alike been produced from a
similar living filament" (p. 236); and again he expresses the conjecture
that one and the same kind of living filament is and has been the cause
of all organic life (p. 244). It does not follow that he was a
"spermist," since he strongly argued against the incasement or
"evolution" theory of Bonnet.

2. Changes produced by differences of climate and even seasons. Thus
"the sheep of warm climates are covered with hair instead of wool, and
the hares and partridges of the latitudes which are long buried in snow
become white during the winter months" (p. 234). Only a passing
reference is made to this factor, and the effects of domestication are
but cursorily referred to. In this respect Darwin's views differed much
from Buffon's, with whom they were the primary causes in the
modification of animals.

The other factors or agencies are not referred to by Buffon, showing
that Darwin was not indebted to Buffon, but thought out the matter in
his own independent way.

3. "Fifthly, from their first rudiment or primordium to the termination
of their lives, all animals undergo perpetual transformations, which are
in part produced by their own exertions in consequence of their desires
and aversions, of their pleasures and their pains, or of irritations or
of associations; and many of these acquired forms or propensities are
transmitted to their posterity" (p. 237). The three great objects of
desire are, he says, "lust, hunger, and security" (p. 237).

4. Contests of the males for the possession of the females, or law of
battle. Under the head of desire he dwells on the desire of the male for
the exclusive possession of the female; and "these have acquired weapons
to combat each other for this purpose," as the very thick, shield-like
horny skin on the shoulders of the boar, and his tusks, the horns of the
stag, the spurs of cocks and quails. "The final cause," he says, "of
this contest among the males seems to be that the strongest and most
active animal should propagate the species, which should thence become
improved" (p. 238). This savors so strongly of sexual selection that we
wonder very much that Charles Darwin repudiated it as "erroneous." It is
not mentioned by Lamarck, nor is Dr. Darwin's statement of the exertions
and desires of animals at all similar to Lamarck's, who could not have
borrowed his ideas on appetency from Darwin or any other predecessor.

5. The transmission of characters acquired during the lifetime of the
parent. This is suggested in the following crude way:

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