At first glance it may seem that the crossing would be impossible for men who were without boats. Such was not the case. In winter the Bering Sea often freezes over completely. Present-day Eskimos cross on the ice and only a few years ago a white man made the crossing with a dog team. Thus, primitive man needed only the winter ice in order to satisfy his curiosity about the land across the water. The journey was made even less hazardous by two islands, the Diomedes, that raised their heads in the center of the Bering Sea, cutting the crossing into two shorter jumps.
It is even possible that when those men reached that tip of Asia no water separated them from America. A strip of land may have connected the two continents. It is known very definitely that at some not far distant date the two continents were connected by land, for some of our well-known animals have crossed from one to the other. The horse and the camel developed in America and walked off to Asia. The mammoth and the bison reversed the direction and crossed from Asia to America. In order for those beasts to make the crossing, a land bridge was necessary.
When the land bridge disappeared is not known. When the first men came is not known. Certain it is, however, that if the land bridge was in existence when the first men came to America, it afforded them an easy approach. If, on the other hand, it had disappeared beneath the waves of the Bering Sea, the men must have crossed on the ice. No one can as yet be positive as to the exact manner of the crossing. The important point is that the crossing was made and America was discovered and populated. Primitive man, after hundreds of thousands of years of wandering over the Old World, had at last found the one point at which he could enter a new land.
That this new land was superior to the old soon became apparent to the newcomers. Summers were longer: winters were less severe. Hunting and fishing were excellent and in the summer edible plants were common. Truly, here was a better land.
The first crossing from Asia to America was made many thousands of years ago. From the evidence now at hand, fifteen or twenty thousand years seems to be not too great an antiquity for those first Americans. Even at that early date, however, man was well-developed mentally and physically and had all the capabilities of modern man. The first American was no primitive brute. He was Homo sapiens, little different from the fifteenth century foreigners who rediscovered America thousands of years later and gradually edged it away from its first settlers.
Primitive human remains, such as those which have been found in the Old World, have never been found in America. Man went through his developmental stages in the Old World and came to America at a late date, a fully developed human being. Pithecanthropus erectus, Sinanthropus, Homo neanderthalensis—America has never known those tongue-twisting lowbrows!
After the first discovery of the new land there were innumerable rediscoveries. One group of men after another came to America and those migrations continued for thousands of years. The latest migrants came to America very recently. Thus, America was populated by many successive waves of migration over a long period of time.
It seems, almost, that after the first group came, word may have spread from one small tribe to another that off to the east lay a better land. People were disappearing over the eastern horizon. What lay in that direction? Curiosity urged them on!
It is altogether possible that actual word of the new land in the east went back to the Asiatic continent. Perhaps there were small counter migrations or perhaps some small traveling group, feeling a bond with some other group in the old country, sent runners back to beckon them on.
Certain it is that there was not just a single migration. Numerous groups of men filtered into America over a period of thousands of years. Slowly, aimlessly, they wandered. One group pushed another and was in turn pushed by an oncoming tribe. After a time, North and South America were covered with hundreds of small tribes of Indians.