It is admitted by all who are acquainted with the history of biology
that the general idea of organic evolution as expressed in the Doctrine
of Descent was quite familiar to Darwin's grandfather, and to others
before and after him, as we have briefly indicated. It must also be
admitted that some of these pioneers of evolutionism did more than apply
the evolution-idea as a modal formula of becoming, they began to inquire
into the factors in the process. Thus there were pre-Darwinian theories
of evolution, and to these we must now briefly refer. (See Prof. W.A.
Locy's "Biology and its Makers". New York, 1908. Part II. "The Doctrine
of Organic Evolution".)
In all biological thinking we have to work with the categories
Organism--Function--Environment, and theories of evolution may be
classified in relation to these. To some it has always seemed that the
fundamental fact is the living organism,--a creative agent, a striving
will, a changeful Proteus, selecting its environment, adjusting
itself to it, self-differentiating and self-adaptive. The necessity of
recognising the importance of the organism is admitted by all Darwinians
who start with inborn variations, but it is open to question whether the
whole truth of what we might call the Goethian position is exhausted in
the postulate of inherent variability.
To others it has always seemed that the emphasis should be laid on
Function,--on use and disuse, on doing and not doing. Practice makes
perfect; c'est a force de forger qu'on devient forgeron. This is one of
the fundamental ideas of Lamarckism; to some extent it met with Darwin's
approval; and it finds many supporters to-day. One of the ablest
of these--Mr Francis Darwin--has recently given strong reasons for
combining a modernised Lamarckism with what we usually regard as sound
Darwinism. (Presidential Address to the British Association meeting at
Dublin in 1908.)
To others it has always seemed that the emphasis should be laid on the
Environment, which wakes the organism to action, prompts it to change,
makes dints upon it, moulds it, prunes it, and finally, perhaps, kills
it. It is again impossible to doubt that there is truth in this
view, for even if environmentally induced "modifications" be not
transmissible, environmentally induced "variations" are; and even if
the direct influence of the environment be less important than
many enthusiastic supporters of this view--may we call them
Buffonians--think, there remains the indirect influence which Darwinians
in part rely on,--the eliminative process. Even if the extreme view
be held that the only form of discriminate elimination that counts is
inter-organismal competition, this might be included under the rubric of
the animate environment.
In many passages Buffon (See in particular Samuel Butler, "Evolution
Old and New", London, 1879; J.L. de Lanessan, "Buffon et Darwin",
"Revue Scientifique", XLIII. pages 385-391, 425-432, 1889.) definitely
suggested that environmental influences--especially of climate and
food--were directly productive of changes in organisms, but he did not
discuss the question of the transmissibility of the modifications so
induced, and it is difficult to gather from his inconsistent writings
what extent of transformation he really believed in. Prof. Osborn
says of Buffon: "The struggle for existence, the elimination of the
least-perfected species, the contest between the fecundity of certain
species and their constant destruction, are all clearly expressed in
various passages." He quotes two of these (op. cit. page 136.):
"Le cours ordinaire de la nature vivante, est en general toujours
constant, toujours le meme; son mouvement, toujours regulier, roule
sur deux points inebranlables: l'un, la fecondite sans bornes donnee
a toutes les especes; l'autre, les obstacles sans nombre qui reduisent
cette fecondite a une mesure determinee et ne laissent en tout temps
qu'a peu pres la meme quantite d'individus de chaque espece"... "Les
especes les moins parfaites, les plus delicates, les plus pesantes,
les moins agissantes, les moins armees, etc., ont deja disparu ou
disparaitront."
Erasmus Darwin (See Ernst Krause and Charles Darwin, "Erasmus Darwin",
London, 1879.) had a firm grip of the "idea of the gradual formation and
improvement of the Animal world," and he had his theory of the process.
No sentence is more characteristic than this: "All animals undergo
transformations which are in part produced by their own exertions, in
response to pleasures and pains, and many of these acquired forms or
propensities are transmitted to their posterity." This is Lamarckism
before Lamarck, as his grandson pointed out. His central idea is that
wants stimulate efforts and that these result in improvements, which
subsequent generations make better still. He realised something of the
struggle for existence and even pointed out that this advantageously
checks the rapid multiplication. "As Dr Krause points out, Darwin just
misses the connection between this struggle and the Survival of the
Fittest." (Osborn op. cit. page 142.)
Lamarck (1744-1829) (See E. Perrier "La Philosophie Zoologique avant
Darwin", Paris, 1884; A. de Quatrefages, "Darwin et ses Precurseurs
Francais", Paris, 1870; Packard op. cit.; also Claus, "Lamarck als
Begrunder der Descendenzlehre", Wien, 1888; Haeckel, "Natural History
of Creation", English translation London, 1879; Lang "Zur Charakteristik
der Forschungswege von Lamarck und Darwin", Jena, 1889.) seems to have
thought out his theory of evolution without any knowledge of Erasmus
Darwin's which it closely resembled. The central idea of his theory
was the cumulative inheritance of functional modifications. "Changes
in environment bring about changes in the habits of animals. Changes in
their wants necessarily bring about parallel changes in their habits. If
new wants become constant or very lasting, they form new habits, the new
habits involve the use of new parts, or a different use of old
parts, which results finally in the production of new organs and the
modification of old ones." He differed from Buffon in not attaching
importance, as far as animals are concerned, to the direct influence of
the environment, "for environment can effect no direct change whatever
upon the organisation of animals," but in regard to plants he agreed
with Buffon that external conditions directly moulded them.
Treviranus (1776-1837) (See Huxley's article "Evolution in Biology",
"Encyclopaedia Britannica" (9th edit.), 1878, pages 744-751, and Sully's
article, "Evolution in Philosophy", ibid. pages 751-772.), whom Huxley
ranked beside Lamarck, was on the whole Buffonian, attaching chief
importance to the influence of a changeful environment both in modifying
and in eliminating, but he was also Goethian, for instance in his idea
that species like individuals pass through periods of growth, full
bloom, and decline. "Thus, it is not only the great catastrophes of
Nature which have caused extinction, but the completion of cycles
of existence, out of which new cycles have begun." A characteristic
sentence is quoted by Prof. Osborn: "In every living being there exists
a capability of an endless variety of form-assumption; each possesses
the power to adapt its organisation to the changes of the outer world,
and it is this power, put into action by the change of the universe,
that has raised the simple zoophytes of the primitive world to
continually higher stages of organisation, and has introduced a
countless variety of species into animate Nature."
Goethe (1749-1832) (See Haeckel, "Die Naturanschauung von Darwin, Goethe
und Lamarck", Jena, 1882.), who knew Buffon's work but not Lamarck's, is
peculiarly interesting as one of the first to use the evolution-idea as
a guiding hypothesis, e.g. in the interpretation of vestigial structures
in man, and to realise that organisms express an attempt to make a
compromise between specific inertia and individual change. He gave the
finest expression that science has yet known--if it has known it--of
the kernel-idea of what is called "bathmism," the idea of an "inherent
growth-force"--and at the same time he held that "the way of life
powerfully reacts upon all form" and that the orderly growth of form
"yields to change from externally acting causes."
Besides Buffon, Erasmus Darwin, Lamarck, Treviranus, and Goethe,
there were other "pioneers of evolution," whose views have been often
discussed and appraised. Etienne Geoffroy Saint-Hilaire (1772-1844),
whose work Goethe so much admired, was on the whole Buffonian,
emphasising the direct action of the changeful milieu. "Species
vary with their environment, and existing species have descended by
modification from earlier and somewhat simpler species." He had a
glimpse of the selection idea, and believed in mutations or sudden
leaps--induced in the embryonic condition by external influences. The
complete history of evolution-theories will include many instances
of guesses at truth which were afterwards substantiated, thus the
geographer von Buch (1773-1853) detected the importance of the Isolation
factor on which Wagner, Romanes, Gulick and others have laid great
stress, but we must content ourselves with recalling one other pioneer,
the author of the "Vestiges of Creation" (1844), a work which passed
through ten editions in nine years and certainly helped to harrow the
soil for Darwin's sowing. As Darwin said, "it did excellent service in
this country in calling attention to the subject, in removing prejudice,
and in thus preparing the ground for the reception of analogous views."
("Origin of Species" (6th edition), page xvii.) Its author, Robert
Chambers (1802-1871) was in part a Buffonian--maintaining
that environment moulded organisms adaptively, and in part a
Goethian--believing in an inherent progressive impulse which lifted
organisms from one grade of organisation to another.