The Life and Letters of Darwin, Vol. 1 HTML version
The Growth Of The 'Origin Of Species'
[The growth of the 'Origin of Species' has been briefly described in my father's words
(above). The letters given in the present and following chapters will illustrate and amplify
the history thus sketched out.
It is clear that in the early part of the voyage of the "Beagle" he did not feel it inconsistent
with his views to express himself in thoroughly orthodox language as to the genesis of
new species. Thus in 1834 he wrote (MS. Journals, page 468.) at Valparaiso: "I have
already found beds of recent shells yet retaining their colour at an elevation of 1300 feet,
and beneath, the level country is strewn with them. It seems not a very improbable
conjecture that the want of animals may be owing to none having been created since this
country was raised from the sea."
This passage does not occur in the published 'Journal,' the last proof of which was
finished in 1837; and this fact harmonizes with the change we know to have been
proceeding in his views. But in the published 'Journal' we find passages which show a
point of view more in accordance with orthodox theological natural history than with his
later views. Thus, in speaking of the birds Synallaxis and Scytalopus (1st edition page
353; 2nd edition page 289), he says: "When finding, as in this case, any animal which
seems to play so insignificant a part in the great scheme of nature, one is apt to wonder
why a distinct species should have been created."
A comparison of the two editions of the 'Journal' is instructive, as giving some idea of the
development of his views on evolution. It does not give us a true index of the mass of
conjecture which was taking shape in his mind, but it shows us that he felt sure enough of
the truth of his belief to allow a stronger tinge of evolution to appear in the second
edition. He has mentioned in the Autobiography that it was not until he read Malthus that
he got a clear view of the potency of natural selection. This was in 1838--a year after he
finished the first edition (it was not published until 1839), and five years before the
second edition was written (1845). Thus the turning-point in the formation of his theory
took place between the writing of the two editions.
I will first give a few passages which are practically the same in the two editions, and
which are, therefore, chiefly of interest as illustrating his frame of mind in 1837.
The case of the two species of Molothrus (1st edition page 61; 2nd edition page 53) must
have been one of the earliest instances noticed by him of the existence of representative
species--a phenomenon which we know ('Autobiography,') struck him deeply. The
discussion on introduced animals (1st edition page 139; 2nd edition page 120) shows how
much he was impressed by the complicated interdependence of the inhabitants of a given
An analogous point of view is given in the discussion (1st edition page 98; 2nd edition
page 85) of the mistaken belief that large animals require, for their support, a luxuriant