CREATION BY EVOLUTION
are mammals of northern type, which compose the second group mentioned above. This group includes the tapirs, the peccaries (or wild swine), the guanacos and llamas, many species of deer, cats great and small, wolves, skunks, weasels, otters, and raccoon-like animals, together with North American types of rodents, rabbits, squirrels, rats, mice, and the like. Though some of the animals of this group are obviously related to those of North America and Asia, nearly all are assigned to different species from their relatives that inhabit those regions, many even to peculiar genera. South American wolves, for example, are in many ways peculiar and must be placed in genera not found in other regions, but that they are related to the northern wolves is indisputable, whether we regard that relationship as ideal or real. If each of these species was created separately, their distribution is in no way explained by the history of the groups to which they belong. If, on the other hand, they arose by natural descent from a common ancestry, this history does explain the distribution, and in a most convincing manner.
Now let us go back to the time, in the middle of the Tertiary period, in the Miocene epoch, when North and South America were not connected, a fact demonstrated by the geological record of Central America and the Isthmus of Panama. We are now in a position to make a full and accurate comparison of the quadrupeds of the two Americas at that time because in Patagonia, on the one hand, and on our Great Plains, on the other, we have immense areas of soft rocks, accumulated at approximately the same time, which have in both the Americas yielded large numbers of well preserved fossil mammals. The separation of the two continents at that time is reflected in the complete difference of their mammals; in their mammalian life North and South America had literally nothing in common. Miocene Pata-
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