CREATION BY EVOLUTION
the pointed snout in some of these fishes became longer. Toward the end of the Cretaceous period (represented by the Chalk), the snout is much elongated and occasionally forms even a sharp blade, as deadly as that of some existing sword fishes. The increasing power of the snout was thus acquired by gradual growth, which can be followed in the fossils stage by stage.
Among land mammals, or quadrupeds, the deer are very interesting for the same reason. Fossils show that the earliest deer had no horns, or antlers. The next deer had small antlers, but none of them were forked more than once. A little later, in the Tertiary period, some of the deer had antlers with from two to four prongs. In the later part of the Pliocene epoch, in the Tertiary period, some of the deer, when full-grown, had antlers even larger and more complex than any deer existing at the present day. Indeed, it is probable that these deer were handicapped by their over-grown antlers and so died out.
Overgrowth of a part that has begun to show progressive enlargement is often observed among fossils. The gigantic tusks of the elephants that lived in late Pliocene and Pleistocene times are further examples. Also the great canine teeth of the sabre-toothed tigers, which lived with them. In both these animals the enlargement was doubtless a hindrance and eventually helped to put an end to them. Excessive enlargement of this kind must have been usually a hindrance, but there is one great enlargement, already mentioned, which proved to be an advantage — that of the brain in mammals. The great growth of the brain which led to the appearance of man, with his superior mental equipment, was the natural result of the progressive development of the brain in the higher mammals during the Tertiary epoch. Though the fossil apes were very different from modern
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