CREATION BY EVOLUTION
long ago led to the belief that birds and reptiles have more in common than any other two classes of vertebrates. A study of comparative anatomy alone shows that birds are, as has been said, little more than “glorified reptiles,” differing from other reptiles mainly in the possession of feathers and wings. Blood precipitation tests support this conclusion; the blood chemistry of the two classes indicates that they are closely related. Embryology reveals the fact that birds, long before they are hatched, have the beginnings of typically reptilian teeth, which never reach maturity. The eggs, embryonic membranes, and indeed the whole course of the embryonic history of birds, is strikingly reptilian. In fact, it is only in later stages of embryonic development that the true avian characters begin to appear. The most characteristically avian feature of a bird consists of its feathers; but even these show by their development that they are no more than finely subdivided reptilian scales.
If, then, birds are specialized descendants of reptiles, it is obvious that there must have been transitional stages leading from reptiles to birds; and it is just here that palaeontology furnishes the evidence that settles the question. In a deposit of Bavarian shale there have been found two nearly complete and well-preserved fossil specimens of a kind of animal that is hard to classify as either reptile or bird, for it obviously possesses some of the features of both. This extinct animal, which is known as Archaeopteryx, is an animal half-way between a reptile and a bird. It had true feathers and it had fore limbs that are half wings and half fore legs, each having three long, prehensile fingers. It had a long, slender lizard-like tail, on which there was a lateral fringe of large feathers. The head was essentially reptilian, having no horny beak but a full set of reptilian teeth. What better evidence could one wish that the birds have been derived from
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