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The geological record of our planet informs us that life first appeared on the earth in simple forms; that these simple forms were, in the course of ages, succeeded by numberless varieties of plants and animals, whose organisation, as new types successively appeared, became, as a general rule, more and more highly specialised, until at last Man appeared upon the scene.
Embryology seems to tell a similar story. The embryo of every mammal, including man, presents in its growth from the germ - cell to maturity, phases similar to those in the embryos of other organisms less highly specialised ; in other words, the foetus of each succeeding type resembles, in at least the earlier stages of its growth, that of its antecessor, and only as maturity approaches does it assume its own special characteristics.
These facts are summed up in ORGANIC EVOLUTION ; and, according
according to Darwin, NATURAL SELECTION was the means by which evolution was brought about. Evolution is thus quite distinct from natural selection.
Evolution is an accepted fact, but it is denied that evolution was brought about by natural selection. The succession of different types, and the fundamental similarity in organisation between any race and its antecessor in the same line of evolution, are established facts confirmed by the continuous discoveries of science, and it is Darwin's glory that he made them familiar to the public mind; but evidence of evolution does not prove that evolution was brought about by natural selection; neither does it establish the truth of natural selection to show that the Mosaic cosmogony
is not in accordance with the facts of geology.
Until the middle of last century the Mosaic account of the creation of animals and plants was generally accepted and stoutly upheld by dogmatic theology; but in 1859 Darwin made public his theory of the evolution of species from the first simple forms of life by natural causes, and this theory, after much controversy, became, and is still, widely accepted as the explanation of the phenomena in the evolution of life on our globe.
Darwin did not formulate his theory, but after setting forth at great length the facts and considerations on which his conclusions were based, declared himself to be thoroughly convinced that all animals and plants were descended from a few progenitors (whose existence he assumed), modified by secondary causes, through a long course of descent, and by “spontaneous variation.”
To facilitate comparison of the two theories we propose, first, to submit our theory of evolution, and then to discuss the operation of Darwin's secondary causes, and his interpretations of the phenomena on which his theory is based