CREATION BY EVOLUTION
the various breeds differ more widely than some wild species, and the changes made under domestication have been far more rapid than those which occur among horses in a natural state. Among wild horses the changes that occur in a thousand years, or even in a million years, may be slight, but by successive changes from age to age we proceed from the tiny four-toed horse of Eocene time to the large single-toed horse of to-day. Every year has revealed more and more intermediate forms, until the fact of the gradual evolution of the horse is now recognized by all biologists.
The Elephant
The elephant is not only the largest living land animal but the most peculiarly built. Its wonderful prehensile trunk and its long, heavy tusks are its most striking features. (See Fig. 3.) It has relatively short and straight legs, a short body, and a very short neck, so that its head is carried high above the ground; its lower jaw is short, it has no front teeth, and only one grinding or cheek tooth in each jaw. Each grinding tooth is composed of 17 to 25 plates and weighs 15 to 20 pounds. Elephants’ teeth are so large and hard that they form fossils which are easily recognized. Fossil teeth and bones of elephants and of their relatives, the mastodons, have been found in North America, South America, and Europe, countries in which elephants no longer live, as well as in Asia and Africa. The elephants appear to have always lived in dense forests and to have fed on the vegetation they afforded.
Only two species of elephants are living to-day, the African and the Indian elephant, but in the Ice Age, which occurred in the Pleistocene epoch, there were more than twenty species. In the Pliocene and Miocene epochs there were few true elephants but many mastodons, and they inhabited all
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