Before Columbus - 1

II

Where the first humans in the Americas came from and how they got to their new homes are now probably the least controversial of these age-old questions. Although at one time or another seemingly all the comers of Europe, Asia, the Middle East, and Africa fancifully have been suggested as the sources of early populations in the New World, no one any longer seriously doubts that the first human inhabitants of North and South America were the descendants of much earlier emigrants from ancestral homelands in northeastern Asia.

It conventionally is said that the migration (or migrations) to North America from Asia took place over the land bridge that once connected the two continents across what are now the Bering and Chukchi seas. "Land bridge" is a whopping misnomer, however, unless one imagines a bridge immensely wider than it was long, more than a thousand miles wide, in fact-about the distance between New York and Omaha-compared with a lengthwise span across the Bering Strait today of less than sixty miles.

During most, and perhaps all of the time from about 80,000 B.C. to about 10,000 B.C. (the geologic era known as the Wisconsin glaciation), at least part of the shallow floor of the Bering and Chukchi seas, like most of the world's continental shelves, was well above sea level due to the capture of so much of the earth's ocean water by the enormous continentwide glaciers of this Ice Age epoch. The effect of this was, for all practical purposes, the complete fusion of Asia and North America into a single land mass whose place of connection was a huge chunk of earth-actually a subcontinent-hundreds of thousands of square miles in size, now called by geographers Berengia.¹⁰ What we see today as a scattering of small islands in the ocean separating Alaska and northeast Asia as far south as the Kamchatka Peninsula are merely the tips of low mountains that, during the Wisconsin glaciation, rose from what at that time was an exposed floor of land.

The first humans in North America, then, appear to have been successor populations to groups of hunters from northern Asia who had moved, as part of the normal continuum of their boundary-less lives, into Berengia and then on to Alaska in pursuit of game and perhaps new vegetative sources of sustenance. During these many thousands of years much of Berengia, like most of Alaska at that time, was a grassland-like tundra, meandering through mountain valleys and across open plains that were filled with wooly mammoths, yaks, steppe antelopes, and many other animals and plants more than sufficient to sustain stable communities of late Paleolithic hunters and gatherers.

To say that the first people of the Americas "migrated" to North America from Asia is thus as much a misconception as is the image of the Berengian subcontinent as a "bridge." For although the origins of the earliest Americans can indeed ultimately be traced back to Asia (just as Asian and European origins ultimately can be traced back to Africa), the now-submerged land that we refer to as Berengia was the homeland of innumerable communities of these people for thousands upon thousands of years-for a span of time, for example, many times greater than that separating our world of today from the pre-Egyptian dawn of Near Eastern civilization more than fifty centuries ago. If anything, then, the direct precursors of American Indian civilizations were the Berengians, the ancient peoples of a once huge and bounteous land that now lies beneath the sea.

During most of the time that Berengia was above sea level, virtually the entire northernmost tier of North America was covered by an immensely thick mantle of glacial ice. As the earth's climate warmed, near the end of the geologic era known as the Pleistocene, the Wisconsin glaciation gradually began drawing to a close, a process that itself took thousands of years. It is estimated, for instance, that it took more than 4000 years for the dissolving ice barrier to creep north from what now is Hartford, Connecticut to St. Johnsbury, Vermont-a distance of less than 200 miles. With the partial melting of the great frozen glaciers, some of the water they had imprisoned was unlocked, trickling into the ocean basins and, over a great stretch of time, slowly lifting world-wide sea levels up hundreds of feet. As the water rose it began ebbing over and eventually inundating continental shelves once again, along with other relatively lowlying lands throughout the globe, including most of Berengia.

The natives of Berengia, who probably never noticed any of these gross geologic changes, so gradual were they on the scale of human time perception, naturally followed the climate-dictated changing shape of the land. Finally, at some point, Asia and North America became separate continents again, as they had been many tens of thousands of years earlier. Berengia was no more. And those of her inhabitants then living in the segregated Western Hemisphere became North America's indigenous peoples, isolated from the rest of the world by ocean waters on every side. Apart from the possible exception of a chance encounter with an Asian or Polynesian raft or canoe from time to time (possible in theory only, there is as yet no good evidence that such encounters ever actually occurred), the various native peoples of the Americas lived from those days forward, for thousands upon thousands of years, separate from the human life that was evolving and migrating about on the rest of the islands and continents of the earth.¹¹

Much more controversial than the issue of where the first peoples of the Americas came from and how they got to the Western Hemisphere are the questions of when they originally moved from Berengia into North and South America-and how many people were resident in the New World when Columbus arrived in 1492. Both these subjects have been matters of intense scholarly scrutiny during the past several decades, and during that rime both of them also have undergone revolutions in terms of scholarly knowledge. Until the 1940s, for example, it commonly was believed that the earliest human inhabitants of the Americas had migrated from the Alaskan portion of Berengia down into North and then South America no more than 6000 years ago. It is now recognized as beyond doubt, however, that numerous complex human communities existed in South America at least 13,000 years ago and in North America at least 6000 years before that. These are absolute minimums. Very recent and compelling archaeological evidence puts the date for earliest human habitation in Chile at 32,000 B.C. or earlier and North American habitation at around 40,000 B.C., while some highly respected scholars contend that the actual first date of human entry into the hemisphere may have been closer to 70,000 B.C.¹²

Similarly dramatic developments have characterized scholarly estimates of the size of the pre-Columbian population of the Americas. In the 1940s and 1950s conventional wisdom held that the population of the entire hemisphere in 1492 was little more than 8,000,000-with fewer than 1,000,000 people living in the region north of present-day Mexico. Today, few serious students of the subject would put the hemispheric figure at less than 75,000,000 to 100,000,000 (with approximately 8,000,000 to 12,000,000 north of Mexico), while one of the most well-regarded specialists in the field recently has suggested that a more accurate estimate would be around 145,000,000 for the hemisphere as a whole and about 1 8,000,000 for the area north of Mexico.¹³