CREATION BY EVOLUTION
The front teeth were reduced in number, those which remained becoming tusks, found in the lower as well as the upper jaw and first used for digging. Ultimately the lower tusks were suppressed, the lower jaw was shortened, and the upper tusks became enormously developed, to serve as weapons and to present a firm surface across which the trunk could break torn-off branches into pieces. The grinding teeth also became fewer and at the same time larger and more complex, to constitute an effective milling apparatus for crushing tough vegetable food. In an adult Indian or African elephant only four of these enormous teeth are in place at the same time, and each of them consists of three substances of different degrees of hardness, which wear unequally, so that the crown is always kept rough, for if smooth it would not be an efficient grinding surface. The densest of the three substances, the enamel, projects in a series of transverse ridges, narrower and more numerous in the Indian species than in its African cousin.
The head has necessarily become large and heavy, having to support the massive trunk and huge teeth (tusks and grinders) and to give attachment to the complicated muscles of the trunk and the large muscles by which the lower jaw is moved up and down in chewing. A long neck is obviously incompatible with so large a head, though the weight of this is less than might have been expected, for the unusually thick wall of the skull is not solid but is traversed by complicated air spaces.
The story of the Elephant, thus briefly outlined, is sufficient in itself to prove the evolution of that particular order of mammals, and a similar story could be told of other orders of that class and of many other groups, both high and low.
Since the time of Darwin and Wallace, the doctrine of evolution has permeated and revolutionized every depart-
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