Lamarck, the Founder of Evolution

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"This fact, as our collection of fossils proves, should lead us to
suppose that the fossil remains of the animals whose living
analogues we know are the less ancient fossils. The species to which
each of them belongs had doubtless not yet time to vary in any of
its forms.

"We should, then, never expect to find among the living species the
totality of those that we meet with in the fossil state, and yet we
cannot conclude that any species can really be lost or extinct. It
is undoubtedly possible that among the largest animals some species
have been destroyed as a result of the multiplication of man in the
regions where they live. But this conjecture cannot be based on the
consideration of fossils alone; we can only form an opinion in this
respect when all the inhabited parts of the globe will have become
perfectly known."

Lamarck did not have, as we now have, a knowledge of the geological
succession of organic forms. The comparatively full and detailed view
which we possess of the different vast assemblages of plant and animal
life which have successively peopled the surface of our earth is a
vision on which his eyes never rested. His slight, piecemeal glimpse of
the animal life of the Paris Basin, and of the few other extinct forms
then known, was all he had to depend upon or reason from. He was not
disposed to believe that the thread of life once begun in the earliest
times could be arbitrarily broken by catastrophic means; that there was
no relation whatever between the earlier and later faunas. He utterly
opposed Cuvier's view that species once formed could ever be lost or
become extinct without ancestors or descendants. He on the contrary
believed that species underwent a slow modification, and that the fossil
forms are the ancestors of the animals now living. Moreover, Lamarck was
the inventor of the first genealogical tree; his phylogeny, in the
second volume of his _Philosophie zoologique_ (p. 463), proves that he
realized that the forms leading up to the existing ones were practically
extinct, as we now use the word. Lamarck in theory was throughout, as
Houssay well says, at one with us who are now living, but a century
behind us in knowledge of the facts needed to support his theory.

In this first published expression of his views on palaeontology, we find
the following truths enumerated on which the science is based: (1) The
great length of geological time; (2) The continuous existence of animal
life all through the different geological periods without sudden total
extinctions and as sudden recreations of new assemblages; (3) The
physical environment remaining practically the same throughout in
general, but with (4) continual gradual but not catastrophic changes in
the relative distribution of land and sea and other modifications in the
physical geography, changes which (5) caused corresponding changes in
the habitat, and (6) consequently in the habits of the living beings; so
that there has been all through geological history a slow modification
of life-forms.

Thus Lamarck's idea of creation is _evolutional_ rather than
_uniformitarian_. There was, from his point of view, not simply a
uniform march along a dead level, but a progression, a change from the
lower or generalized to the higher or specialized--an evolution or
unfolding of organic life. In his effort to disprove catastrophism he
failed to clearly see that species, as we style them, became extinct,
though really the changes in the species practically amounted to
extinctions of the earlier species as such. The little that was known
to Lamarck at the time he wrote, prevented his knowing that species
became extinct, as we say, or recognizing the fact that while some
species, genera, and even orders may rise, culminate, and die, others
are modified, while a few persist from one period to another. He did,
however, see clearly that, taking plant and animal life as a whole, it
underwent a slow modification, the later forms being the descendants of
the earlier; and this truth is the central one of modern palaeontology.

Lamarck's first memoir on fossil shells, in which he described many new
species, was published in 1802, after the appearance of his
_Hydrogeologie_, to which he refers. It was the first of a series of
descriptive papers, which appeared at intervals from 1802 to 1806. He
does not fail to open the series of memoirs with some general remarks,
which prove his broad, philosophic spirit, that characterizing the
founder of a new science. He begins by saying that the fossil forms have
their analogues in the tropical seas. He claims that there was evident
proof that these molluscs could not have lived in a climate like that of
places in which they now occur, instancing _Nautilius pompilius_, which
now lives in the seas of warm countries; also the presence of exotic
ferns, palms, fossil amber, fossil gum elastic, besides the occurrence
of fossil crocodiles and elephants both in France and Germany.[83]

Hence there have been changes of climate since these forms flourished,
and, he adds, the intervals between these changes of climate were
stationary periods, whose duration was practically without limit. He
assigns a duration to these stationary or intermediate periods of from
three to five million years each--"a duration infinitely small relative
to those required for all the changes of the earth's surface."

He refers in an appreciative way to the first special treatise on fossil
shells ever published, that of an Englishman named Brander,[84] who
collected the shells "out of the cliffs by the sea-coast between Christ
Church and Lymington, but more especially about the cliffs by the
village of Hordwell," where the strata are filled with these fossils.
Lamarck, working upon collections of tertiary shells from Grignon and
also from Courtagnon near Reims, with the aid of Brander's work showed
that these beds, not known to be Eocene, extended into Hampshire,
England; thus being the first to correlate by their fossils, though in a
limited way to be sure, the tertiary beds of France with those of
England.

How he at a later period (1805) regarded fossils and their relations to
geology may be seen in his later memoirs, _Sur les Fossiles des environs
de Paris_.[85]

"The determination of the characters, both generic and specific, of
animals of which we find the fossil remains in almost all the dry
parts of the continents and large islands of our globe will be, from
several points of view, a thing extremely useful to the progress of
natural history. At the outset, the more this determination is
advanced, the more will it tend to complete our knowledge in regard
to the species which exist in nature and of those which have
existed, as it is true that some of them have been lost, as we have
reason to believe, at least as concerns the large animals. Moreover,
this same determination will be singularly advantageous for the
advancement of geology; for the fossil remains in question may be
considered, from their nature, their condition, and their situation,
as authentic monuments of the revolutions which the surface of our
globe has undergone, and they can throw a strong light on the nature
and character of these revolutions."

This series of papers on the fossils of the Paris tertiary basin
extended through the first eight volumes of the _Annales_, and were
gathered into a volume published in 1806. In his descriptions his work
was comparative, the fossil species being compared with their living
representatives. The thirty plates, containing 483 figures representing
184 species (exclusive of those figured by Brard), were afterwards
published, with the explanations, but not the descriptions, as a
separate volume in 1823.[86] This (the text published in 1806) is the
first truly scientific palaeontological work ever published, preceding
Cuvier's _Ossemens fossiles_ by six years.

When we consider Lamarck's--at his time unrivalled--knowledge of
molluscs, his philosophical treatment of the relations of the study of
fossils to geology, his correlation of the tertiary beds of England with
those of France, and his comparative descriptions of the fossil forms
represented by the existing shells, it seems not unreasonable to regard
him as the founder of invertebrate palaeontology, as Cuvier was of
vertebrate or mammalian palaeontology.

We have entered the claim that Lamarck was one of the chief founders of
palaeontology, and the first French author of a genuine, detailed
palaeontological treatise. It must be admitted, therefore, that the
statement generally made that Cuvier was the founder of this science
should be somewhat modified, though he may be regarded as the chief
founder of vertebrate palaeontology.

In this field, however, Cuvier had his precursors not only in Germany
and Holland, but also in France.

Our information as to the history of the rise of vertebrate palaeontology
is taken from Blainville's posthumous work entitled _Cuvier et Geoffroy
Saint-Hilaire_.[87] In this work, a severe critical and perhaps not
always sufficiently appreciative account of Cuvier's character and work,
we find an excellent history of the first beginnings of vertebrate
palaeontology. Blainville has little or nothing to say of the first steps
in invertebrate palaeontology, and, singularly enough, not a word of
Lamarck's principles and of his papers and works on fossil shells--a
rather strange oversight, because he was a friend and admirer of
Lamarck, and succeeded him in one of the two departments of
invertebrates created at the Museum d'Histoire Naturelle after Lamarck's
death.

Blainville, who by the way was the first to propose the word
_palaeontology_, shows that the study of the great extinct mammals had
for forty years been held in great esteem in Germany, before Faujas and
Cuvier took up the subject in France. Two Frenchmen, also before 1789,
had examined mammalian bones. Thus Bernard de Jussieu knew of the
existence in a fossil state of the teeth of the hippopotamus.
Guettard[88] published in 1760 a memoir on the fossil bones of Aix en
Provence. Lamanon (1780-1783)[89] in a beautiful memoir described a
head, almost entire, found in the gypsum beds of Paris. Daubenton had
also slightly anticipated Cuvier's law of correlation, giving "a very
remarkable example of the mode of procedure to follow in order to solve
these kinds of questions by the way in which he had recognized a bone of
a giraffe whose skeleton he did not possess" (De Blainville).

"But it was especially in Germany, in the hands of Pallas, Camper,
Blumenbach, anatomists and physicians, also those of Walch, Merck,
Hollmann, Esper, Rosenmueller, and Collini (who was not, however,
occupied with natural history), of Beckman, who had even discussed
the subject in a general way (_De reductione rerum fossilium ad
genera naturalia prototyporum--Nov. Comm. Soc. Scient.
Goettingensis_, t. ii.), that palaeontology applied to quadrupeds had
already settled all that pertained to the largest species."

As early as 1764, Hollmann[90] had admirably identified the bones of a
rhinoceros found in a bone-deposit of the Hartz, although he had no
skeleton of this animal for comparison.

Pallas, in a series of memoirs dating from 1773, had discovered and
distinguished the species of Siberian elephant or mammoth, the
rhinoceros, and the large species of oxen and buffalo whose bones were
found in such abundance in the quaternary deposits of Siberia; and, as
Blainville says, if he did not distinguish the species, it was because
at this epoch the question of the distinction of the two species of
rhinoceros and of elephants, in the absence of material, could not be
solved. This solution, however, was made by the Dutch anatomist Camper,
in 1777, who had brought together at Amsterdam a collection of skeletons
and skulls of the existing species which enabled him for the first time
to make the necessary comparisons between the extinct and living
species. A few years later (1780) Blumenbach confirmed Camper's
identification, and gave the name of _Elephas primigenius_ to the
Siberian mammoth.

"Beckman" [says Blainville] "as early as 1772 had even published a
very good memoir on the way in which we should consider fossil
organic bodies; he was also the first to propose using the name
_fossilia_ instead of _petrefacta_, and to name the science which
studies fossils _Oryctology_. It was also he who admitted that these
bodies should be studied with reference to the class, order, genus,
species, as we would do with a living being, and he compared them,
which he called _prototypes_,[91] with their analogues. He then
passes in review, following the zooelogical order, the fossils which
had been discovered by naturalists. He even described one of them as
a new species, besides citing, with an erudition then rare, all the
authors and all the works where they were described. He did no more
than to indicate but not name each species. Thus he was the means of
soon producing a number of German authors who made little advance
from lack of anatomical knowledge; but afterwards the task fell into
the hands of men capable of giving to the newly created palaeontology
a remarkable impulse, and one which since then has not abated."

Blumenbach,[92] the most eminent and all-round German anatomist and
physiologist of his time, one of the founders of anthropology as well as
of palaeontology, had meanwhile established the fact that there were two
species of fossil cave-bear, which he named _Ursus spelaeus_ and _U.
arctoideus_. He began to publish his _Archaeologia telluris_,[93] the
first part of which appeared in 1803.

From Blainville's useful summary we learn that Blumenbach, mainly
limiting his work to the fossils of Hanover, aimed at studying fossils
in order to explain the revolutions of the earth.

"Hence the order he proposed to follow was not that commonly
followed in treatises on oryctology, namely, systematic, following
the classes and the orders of the animal and vegetable kingdom, but
in a chronological order, in such a way as to show that the classes,
so far as it was possible to conjecture with any probability, were
established after or in consequence of the different revolutions of
the earth.

"Thus, as we see, all the great questions, more or less insoluble,
which the study of fossil organic bodies can offer, were raised and
even discussed by the celebrated professor of Goettingen as early as
1803, before anything of the sort could have arisen from the essays
of M. G. Cuvier; the errors of distribution in the classes committed
by Blumenbach were due to the backward state of geology."

The political troubles of Germany, which also bore heavily upon the
University of Goettingen, probably brought Blumenbach's labors to an end,
for after a second "specimen" of his work, of less importance than the
first, the _Archaeologia telluris_ was discontinued.

The French geologist Faujas,[94] who also published several articles on
fossil animals, ceased his labors, and now Cuvier began his memorable
work.

The field of the labors and triumphs of palaeontology were now
transferred to France. We have seen that the year 1793, when Lamarck and
Geoffroy Saint-Hilaire were appointed to fill the new zooelogical chairs,
and the latter had in 1795 called Cuvier from Normandy to Paris, was a
time of renascence of the natural sciences in France. Cuvier began a
course of lectures on comparative anatomy at the Museum of Natural
History. He was more familiar than any one else in France with the
progress in natural science in Germany, and had felt the stimulus
arising from this source; besides, as Blainville stated, he was also
impelled by the questions boldly raised by Faujas in his geological
lectures, who was somewhat of the school of Buffon. Cuvier, moreover,
had at his disposition the collection of skeletons of the Museum, which
was frequently increased by those of the animals which died in the
menagerie. With his knowledge of comparative anatomy, of which, after
Vicq-d'Azyr, he was the chief founder, and with the gypsum quarry of
Montmartre, that rich cemetery of tertiary mammals, to draw from, he had
the whole field before him, and rapidly built up his own vast
reputation and thus added to the glory of France.

His first contribution to palaeontology[95] appeared in 1798, in which he
announced his intention of publishing an extended work on fossil bones
of quadrupeds, to restore the skeletons and to compare them with those
now living, and to determine their relations and differences; but, says
Blainville, in the list of thirty or forty species which he enumerates
in his tableau, none was apparently discovered by him, unless it was the
species of "dog" of Montmartre, which he afterward referred to his new
genera Palaeotherium and Anaplotherium. In 1801 (le 26 brumaire, an IX.)
he published, by order of the Institut, the programme of a work on
fossil quadrupeds, with an increased number of species; but, as
Blainville states, "It was not until 1804, and in tome iii. of the
_Annales du Museum_, namely, more than three years after his programme,
that he began his publications by fragments and without any order, while
these publications lasted more than eight years before they were
collected into a general work"; this "_corps d'ouvrage_" being the
_Ossemens fossiles_, which was issued in 1812 in four quarto volumes,
with an atlas of plates.

It is with much interest, then, that we turn to Cuvier's great work,
which brought him such immediate and widespread fame, in order to see
how he treated his subject. His general views are contained in the
preliminary remarks in his well-known "Essay on the Theory of the Earth"
(1812), which was followed in 1821 by his _Discours sur les Revolutions
de la Surface du Globe_.

It was written in a more attractive and vigorous style than the writings
of Lamarck, more elegant, concise, and with less repetition, but it is
destitute of the philosophic grasp, and is not the work of a profound
thinker, but rather of a man of talent who was an industrious collector
and accurate describer of fossil bones, of a high order to be sure, but
analytical rather than synthetical, of one knowing well the value of
carefully ascertained and demonstrated facts, but too cautious, if he
was by nature able to do so, to speculate on what may have seemed to him
too few facts. It is also the work of one who fell in with the current
views of the time as to the general bearing of his discoveries on
philosophy and theology, believing as he did in the universality of the
Noachian deluge.

Like Lamarck, Cuvier independently made use of the comparative method,
the foundation method in palaeontology; and Cuvier's well-known "law of
correlation of structures," so well exemplified in the vertebrates, was
a fresh, new contribution to philosophical biology.

In his _Discours_, speaking of the difficulty of determining the bones
of fossil quadrupeds, as compared with fossil shells or the remains of
fishes, he remarks:[96]

"Happily comparative anatomy possessed a principle which, well
developed, was capable of overcoming every difficulty; it was that
of the correlation of forms in organic beings, by means of which
each kind of organism can with exactitude be recognized by every
fragment of each of its parts.--Every organized being," he adds,
"forms an entire system, unique and closed, whose organs mutually
correspond, and concur in the same definite action by a reciprocal
reaction. Hence none of these parts can change without the other
being also modified, and consequently each of them, taken
separately, indicates and produces (_donne_) all the others.

"A claw, a shoulder-blade, a condyle, a leg or arm-bone, or any
other bone separately considered, enables us to discover the kind of
teeth to which they have belonged; so also reciprocally we may
determine the form of the other bones from the teeth. Thus,
commencing our investigation by a careful survey of any one bone by
itself, a person who is sufficiently master of the laws of organic
structure can reconstruct the entire animal. The smallest facet of
bone, the smallest apophysis, has a determinate character, relative
to the class, the order, the genus, and the species to which it
belongs, so that even when one has only the extremity of a
well-preserved bone, he can, with careful examination, assisted by
analogy and exact comparison, determine all these things as surely
as if he had before him the entire animal."

Cuvier adds that he has enjoyed every kind of advantage for such
investigations owing to his fortunate situation in the Museum of Natural
History, and that by assiduous researches for nearly thirty years[97]
he has collected skeletons of all the genera and sub-genera of
quadrupeds, with those of many species in certain genera, and several
individuals of certain species. With such means it was easy for him to
multiply his comparisons, and to verify in all their details the
applications of his laws.

Such is the famous law of correlation of parts, of Cuvier. It could be
easily understood by the layman, and its enunciation added vastly to the
popular reputation and prestige of the young science of comparative
anatomy.[98] In his time, and applied to the forms occurring in the
Paris Basin, it was a most valuable, ingenious, and yet obvious method,
and even now is the principal rule the palaeontologist follows in
identifying fragments of fossils of any class. But it has its
limitations, and it goes without saying that the more complete the
fossil skeleton of a vertebrate, or the remains of an arthropod, the
more complete will be our conception of the form of the extinct
organism. It may be misleading in the numerous cases of convergence and
of generalized forms which now abound in our palaeontological
collections. We can well understand how guarded one must be in working
out the restorations of dinosaurs and fossil birds, of the Permian and
Triassic theromorphs, and the Tertiary creodonts as compared with
existing carnivora.

As the late O. C. Marsh[99] observed:

"We know to-day that unknown extinct animals cannot be restored from
a single tooth or claw unless they are very similar to forms already
known. Had Cuvier himself applied his methods to many forms from
the early tertiary or older formations he would have failed. If, for
instance, he had had before him the disconnected fragments of an
eocene tillodont he would undoubtedly have referred a molar tooth to
one of his pachyderms, an incisor tooth to a rodent, and a claw bone
to a carnivore. The tooth of a Hesperornis would have given him no
possible hint of the rest of the skeleton, nor its swimming feet the
slightest clue to the ostrich-like sternum or skull. And yet the
earnest belief in his own methods led Cuvier to some of his most
important discoveries."

Let us now examine from Cuvier's own words in his _Discours_, not
relying on the statements of his expositors or followers, just what he
taught notwithstanding the clear utterances of his older colleague,
Lamarck, whose views he set aside and either ignored or ridiculed.[100]

~ ~ ~ ~ ~

He at the outset affirms that nature has, like mankind, also had her
intestine wars, and that "the surface of the globe has been much
convulsed by successive revolutions and various catastrophes."

As first proof of the revolutions on the surface of the earth he
instances fossil shells, which in the lowest and most level parts of the
earth are "almost everywhere in such a perfect state of preservation
that even the smallest of them retain their most delicate parts, their
sharpest ridges, and their finest and tenderest processes."

"We are therefore forcibly led to believe not only that the sea has
at one period or another covered all our plains, but that it must
have remained there for a long time and in a state of tranquillity,
which circumstance was necessary for the formation of deposits so
extensive, so thick, in part so solid, and filled with the exuviae of
aquatic animals."

But the traces of revolutions become still more marked when we ascend a
little higher and approach nearer to the foot of the great mountain
chains. Hence the strata are variously inclined, and at times vertical,
contain shells differing specifically from those of beds on the plains
below, and are covered by horizontal later beds. Thus the sea, previous
to the formation of the horizontal strata, had formed others, which by
some means have been broken, lifted up, and overturned in a thousand
ways. There had therefore been also at least one change in the basin of
that sea which preceded ours; it had also experienced at least one
revolution.

He then gives proofs that such revolutions have been numerous.

"Thus the great catastrophes which have produced revolutions in the
basins of the sea were preceded, accompanied, and followed by
changes in the nature of the fluid and of the substances which it
held in solution, and when the surface of the seas came to be
divided by islands and projecting ridges, different changes took
place in every separate basin."

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