The science of life : fully illustrated in tone and line and including many diagrams

THE EVIDENCE FROM PLANT

The evidence of the fossils in the rocks is direct evidence for Evolution. But the evidence of embryology, though indirect, is more immediate. You can watch the individual animal indulge in these amazing reminiscences, and pass almost before your eyes from ancestral primitiveness to adult modernity. All the facts have a simple and straightforward meaning if Evolution be a fact, while a denial of Evolution leaves them unexplained and apparently inexplicable. It is plainly essential to a parasite like Sacculina that it should have a free-swimming larva, but it is hard to see why that larva should be built so exactly upon the crustacean plan if Sacculina has no crustacean ancestry. And a colt, safe in its mother’s womb

AND ANIMAL STRUCTURE

until it is born a well-nigh complete miniature of its parents, has no sort of advantages in preceding its backbone by a notochord or producing and reabsorbing gill-arches. Nor is it some mysterious, widespread harmony which requires this rhythm of repetition, because the amount of recapitulation varies with different animals and the story is often blurred and abbreviated. Recapitulation occurs like something done under a powerful and unavoidable inertia of tradition, like something deep in the nature of living creatures. They recapitulate because they reproduce and because they have been evolved through an infinite series of reproductions from simpler things.

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