181. The Route of Entry into the Western Hemisphere
With such background man entered America at Behring Strait. He may have navigated; more likely, or more often, he crossed on the ice. The water distance is only about sixty miles; the Diomede islands lie near the middle of the gap; and the ice may have extended across pretty continuously, ten thousand years nearer the peak of the last glaciation. Long before, there had been a land bridge from Siberia to Alaska, by which horses, camels, cattle, elephants, deer and many other species extended their range from one continent to another. But this was in geological antiquity, man’s entry in geological recency—immediacy, rather; and the divided configuration of the continents was probably already established. Horses had become extinct in the New World when man arrived, the elephant tribe probably also. Llamas, pumas, jaguars took the place of Old World camels, lions, tigers. The fauna of the Americas, their vegetation, their climate, were nearly as they are to-day.
The Aleutian islands have also been suggested as a migration route. But their chain is long, the gap at the western end one of hundreds of miles of open water, scarcely negotiable except to rather expert navigators. Still weaker would be any supposition of arrival from Polynesia. Here the distances between the nearest islands and the mainland run to thousands of miles. Only well-equipped voyagers could survive, and there is nothing to prove positively that even late Palæolithic man had boats. Further, all the Polynesian evidence points to a late settling of the eastern islands of the Pacific; a few thousand years ago at most. Exclusion therefore indicates the Behring route as the only one to be seriously considered.
The migration was scarcely a sudden or single one. It went on for generations, perhaps for thousands of years in driblets. Two or three explorers would set across and return, to be followed by a few families. Others succeeded them. There would be no crowding, for a long time no resistance at the strait on the part of jealous established settlers. The open south, always milder, generally more fruitful the farther one went, lay ahead. It must long have drawn immigrants away from the strait faster than they crossed it. Some of the invading bands almost certainly differed from one another in customs, perhaps perceptibly in appearance, though of one general level of culture.