The Great Divide

Route.
Roughly 30,000–20,000 years ago, the groups that had headed inland from
     Pakistan/India bifurcated, with one group travelling west, towards Europe, while the
     other travelled deep into Siberia, perhaps meeting up with the people moving inland
     from China.
Some time around 25,000–22,000 years ago, humans reached the Bering Land
     Bridge which connected Siberia to Alaska, though there is no archaeological evidence
     for them in Chukotka, or Alaska, until after 15,000 years ago. At that time, the
     world was in the grip of the last Ice Age, which endured from 110,000 years ago to
     about 14,000 years ago and as a result of which much of the world’s water was
     locked away in the great glaciers – many kilometres thick – which
     mantled the Earth. As a consequence, the world’s sea levels had fallen to
     some 400 feet below where they are now. In turn, this meant that the geography of
     the world was substantially different from what it is today. One important –
     crucial, fascinating – effect of this was that the Bering Strait did not then
     exist. It was comprised of dry land, or at least scrub land with lots of ponds and
     lakes but even so very passable for early humans. And so, some time between, roughly
     speaking, 20,000 and 14,000 years ago, early humans migrated into what would be
     called, later, variously the New World, the Americas, or the western hemisphere.
     Then, and this is no less crucial, after 14,000 years ago, when the world warmed up
     and the latest Ice Age came to an end, the Bering Strait refilled with water, Alaska
     and Siberia became parts of different landmasses and the western hemisphere –
     the Americas, the New World – was separated from the Old.
Some of this evidence is shown on maps 1–10. These maps summarise visually
     several of the arguments to be found throughout the text of this book.
     
    As the crow flies (or a 747), it is about 7,500 miles from the southern end
     of the Red Sea to Uelen on the eastern-most tip of Siberia, but beachcombing around
     India and South East Asia would have more than doubled – and even tripled
     – that distance, and cutting across the landmass of Central Asia would not have
     been much shorter, and could have been more arduous, given the mountain ranges and lakes
     and rivers that needed to be circumvented without much in the way of technology. The
     journey of, say, 20,000 miles, took 50,000 years (though until early people reached the
     regions of intense cold, they may have spread quite quickly).
    But eventually, early peoples arrived in what is now known as the Chukotskiy
     Poluostrov, or Chukotskiy Peninsula, overlooking what would become the Bering Strait. It
     is not only the close proximity of Siberia to Alaska that suggests early peoples entered
     the New World in this way (the strait – which was then a landbridge – is
     barely sixty miles wide at its narrowest point). There are three pieces of genetic
     evidence that, taken together, paint a coherent and convincing picture of early
     humankind’s entry into the Americas.
    The Chukchi people of eastern Siberia who, though they might be said to live
     at the edge of the world – the edge of the modern world at any rate – are
     nonetheless central from our point of view. Even today they live by herding reindeer and
     fishing through small holes in the ice-covered rivers. 2 No one really knows why early
     peoples chose to live in this hard part of the world. Perhaps they followed mammoths and
     other big game; perhaps they didn’t choose to live there at all but were
     forced there by population pressures from the west and south. Just how hard life there
     was is confirmed by archaeological studies which show that there is a complete lack of sites in this part of Siberia between 19,000 and 18,000 years ago,
     suggesting that the amount of ice at its most extensive caused the area to be abandoned
     for a time before being re-colonised, by highly mobile hunter-gatherers who frequently
     moved their camps to where important animal resources were available – most sites
     have the remains of just one type of large-bodied prey species: reindeer, red deer or
     bison. Whatever happened, eastern Siberia (still a good distance from Chukotski) has
     been occupied – at sites such as Dyukhtai and Mal’ta – since 20,000
     years ago (see map 5). This date is important, as is the location.
    The date is important because no archaeological sites earlier than