Probably the
most hotly argued subject in archeology is the question of how and when humans
first arrived in the New World. Our goal is to describe the most popular
hypotheses of how people first arrived in the New World and how the lands of
the Aztecs,
Maya, and
Inca were first populated. Dates are
all subject to change and debate. Experts often shift them by tens of thousands
of years as new evidence is presented.
Geologists believe that approximately 30,000 years ago, during the Pleistocene, the Earth was nearing the end of a great climactic change commonly referred to as the Ice Age (though this theory has opponents). During the ice age, temperatures dropped significantly forming incredibly large ice sheets, which spread across the poles of the planet. The ice reached down across northern Europe and all the way down into Iowa and Nebraska in North America. The ice sheets consumed so much of the Earth's water that ocean levels dropped significantly, exposing previously submerged landforms along the coastlines.
The most
important of these exposed land formations occurred where the present-day
waters of the Bering and Chukhin seas separate Alaska from Siberia. A strip of
land, referred to as the Bering Land Bridge, connected North America to Asia.
It is believed that nomadic people of Northern Asia wandered across this bridge
into modern day Alaska, Canada, and the northern United States.
During the next 15,000 years, the descendants of these people spread from the sub-arctic regions of Canada into the far west of the US, across the midlands, the northeastern United States, the southeast, the southwest, and finally into Mesoamerica. The first group crossed into South America approximately 15,000 years ago and by 12,000 years ago people lived in the southern-most regions.
Experts argue as to what survival strategies the first occupants of Mesoamerica used. Why they moved into the new territory, through Latin America and down the Andes, is another controversy. Gordon Willey, armed with evidence of only flakes, scrappers and choppers from the earliest sites, believed that the first occupants moved south into Mexico because of population pressure from the north. He believed that their stone implements were so ineffective that they couldn't have been hunters. He hypothesizes that they lived as scavengers and gatherers, using their tools to butcher carcasses that they found and to chop up roots and vegetables. He believed that their existence was hardly prosperous and that the first occupants were not very successful. Willey believed that the large projectile point used by the big game hunters arrived later and that the remainder of the first occupants either joined them or were killed by them.
Thomas Lynch read the same evidence a different way. He thought that the flake tools were just the remnants of a successful group of hunters that followed the big game into the southern regions and their population exploded as they exploited the untouched food resources. He also believed that the population flowed through Mexico and down the Andes, because that is where all the oldest sites were located.
Recently, though, new evidence suggests that the first migrations into South America may not have been limited to the Andes. A cave in the Amazon Basin has been discovered with remains dating to the earliest period relating to the first migration.
Fagan, Brian M. The Great Journey: The Peopling of Ancient America. Thames and Hudson Ltd, London, 1987.
Jennings, Jesse D., Prehistory of North America. McGraw-Hill Book Co.
St. Louis.
Jennings, Jesse D., Ancient North America. University of Utah, W.H. Freeman & Co., New York.