Origin of Species Variorum

Comparison with 1866

development. In some few cases there may have been what we must call retrogression of organisation. But the main cause lies in the circumstance that under very simple conditions of life a high organisation would be of no service,— possibly would be of actual disservice, as being of a more delicate nature, and more liable to be put out of order and thus injured.

A difficulty, diametrically opposite to this which we have just been considering, has been advanced, namely, that, looking to the dawn of life, when all organic beings, as we may imagine, presented the simplest structure, how could the first steps in advancement or in the differentiation and specialisation of parts have arisen? ↑ Mr. Herbert Spencer would probably answer that as soon as the most simple unicellular organism came by growth or division to be compounded of several cells, or became attached to any supporting surface, his law would come into action, namely, "that homologous units of any order become differentiated in proportion as their relations to incident forces become different." But as we have no facts to guide us, all speculation on the subject is useless. It is, however, an error to suppose that there would be no struggle for existence, and, consequently, no natural selection, until many forms had been produced: variations in a single species inhabiting an isolated station might be beneficial, and, through their preservation, either the whole mass of individuals might become modified, or two distinct forms might arise. But I must recur to what was stated towards the close of the Introduction, where I say that no one ought to feel surprise at much remaining as yet unexplained on the origin of species, if due allowance be made for our profound ignorance on the mutual relations of the inhabitants of the world during the many past epochs in its history.

Text in this page (from subtitle, paragraph 6770 to paragraph 6802, sentence 500, word 39) is not present in 1866

development. In some few cases there has been what we must call retrogression of organisation. But the main cause lies in the fact that under very simple conditions of life a high organisation would be of no service,— possibly would be of actual disservice, as being of a more delicate nature, and more liable to be put out of order and .. injured.

... Looking to the first dawn of life, when all organic beings, as we may believe, presented the simplest structure, how, it has been asked, could the first steps in the advancement or differentiation of parts have arisen? ↑ Mr. Herbert Spencer would probably answer that, as soon as .. simple unicellular organism came by growth or division to be compounded of several cells, or became attached to any supporting surface, his law ... "that homologous units of any order become differentiated in proportion as their relations to incident forces become different" would come into action. But as we have no facts to guide us, .. speculation on the subject is almost useless. It is, however, an error to suppose that there would be no struggle for existence, and, consequently, no natural selection, until many forms had been produced: variations in a single species inhabiting an isolated station might be beneficial, and thus the whole mass of individuals might be modified, or two distinct forms might arise. But, as I remarked towards the close of the Introduction, ... no one ought to feel surprise at much remaining as yet unexplained on the origin of species, if we make due allowance for our profound ignorance on the mutual relations of the inhabitants of the world at the present time, and still more so during past ages. ↑

... Mr. H. C. Watson thinks that I have overrated the importance of divergence of character (in which, however, he apparently believes), and that convergence, .. as it may be called, has likewise played a part. If two species, belonging to two distinct though allied genera, had both produced a large number of new and divergent forms, it is conceivable that these might approach each other so closely that they would have all to be classed under the same .. genus; and thus the descendants of two distinct genera would converge into one. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. But it would in most cases be extremely rash to attribute to convergence a close and general similarity of structure in the modified descendants of widely distinct forms. The shape of a crystal is determined solely by the molecular forces, and it is not surprising that dissimilar substances should sometimes assume the same form; but with organic beings we should bear in mind that the form of