Page:Creation by Evolution (1928).djvu/46

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CREATION BY EVOLUTION

an additional piece due to a pulling out of the upper lip. This is the evolutionary way!

We live in what has sometimes been called the “age of insects,” for of these there are more than a quarter of a million different kinds. Now there must be some meaning in the fact that these can be classified in an orderly way; that one can for many kinds make plausible “genealogical trees.” Often one species, with its varieties, seems to grade into another. In many parts of the animal kingdom there are types that link great classes together. Thus the old-fashioned Peripatus type, a little creature somewhat like a permanent caterpillar, has some worm characters and some centipede characters. It is to some extent a connecting link. The oldest known bird, a fossil beautifully preserved in lithographic stone of Jurassic age, has numerous reptilian features, such as teeth in both jaws, a long lizard-like tail, a half-made wing, and abdominal ribs. Yet it was a genuine feathered bird! And this fossil is unexplainable unless we recognize the fact that this bird had reptilian ancestors.

Very striking, again, are the embryological facts which show that the development of the individual is like a condensed recapitulation of the probable evolution of the race. An embryo bird is for some days almost indistinguishable from an embryo reptile; they progress along the same high-road together; but soon there comes a parting of the ways and each goes off on its own path. The gill-slits of fishes and tadpoles—the slits through which the water used in breathing passes—are persistent in all the embryos of reptiles, birds, and mammals, though in these higher back-boned animals they have nothing to do with respiration. All of them are merely transient passages except the one that becomes the “eustachian tube,” which leads from the ear to the back of the mouth. They are straws which show how

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