How Did Humans First Reach the Americas?
It is believed that the first humans to reach the Americas originated from East Asia and arrived by crossing over the Beringia land bridge which connected Siberia to Alaska approximately 13,500 years ago. The exact route of the journey taken by humans from East Asia to North and South America is still the subject of debate, but evidence from archaeological and genetic research points to the most probable routes taken.
A Brief Look at Beringia
Beringia is the land bridge which connected Siberia and Alaska during the Last Glacial Maximum and formed a natural land corridor through which the first humans were able to migrate to the Americas. It is believed that this land bridge appeared during the glacial maximum due to the fall in sea levels through ocean water being stored in massive continental ice sheets.
At its peak, it is estimated that Beringia covered over 2 million sq km at a maximum width of 1,000 km. Features like exposed islands and steppes supported a variety of life allowing for human survival and sustained them for up to 12,000 km of the journey.
The Spread Of Humans Throughout the Americas
The exact route which humans first used to populate the Americas is still disputed but the most widely accepted theory is that they followed the glaciers south searching for resources and animals to hunt along the way.
It is likely that they first came across the now Canada, then travelled south and ended up in both North and South America. After reaching the two continents, they spread out and gradually populated the entire American continent, reaching as far south as Tierra Del Fuego and forming the many tribes and civilisations we see today.
Types of Archaeological Evidence Used to Date The Migration
Archaeological evidence has been used to learn about the migration of humans to the Americas for some time now. Here are some of the main types of archaeological evidence used to this end.
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Biological Structures: In the early 20th century, it was found that several large mammals, such as mammoths, lived in North America prior to the arrival of humans. This helped to demonstrate that humans had arrived by crossing the Beringia land bridge at some point.
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Artifacts: Artifacts such as spear points have been found in North and South America, which can help to date the presence of humans in those regions. Such objects are usually made of organic materials, however, so the exact age of these artifacts is difficult to calculate.
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Human Remains: The discovery of human remains in Mexico, Peru, and throughout the continent has helped to demonstrate that humans did indeed travel to the Americas by crossing Beringia. Skeletal remains can help to date the arrival of humans to an approximate period.
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Environmental Evidence: Environmental evidence has been used to date the presence of humans on both continents. The presence of various fossils and charcoal deposits can point to humans living in a certain area at a particular time.
Genetic Evidence
In addition to the archaeological evidence, another important field of research on the subject has been genetics. This has allowed for a more in-depth study of the movement of humans to the Americas and the path taken.
By looking at the DNA of modern populations in North, Central, and South America, researchers have been able to identify similarities that can point to a shared ancestry. This has helped to piece together the pathways of migration and confirm that the first humans to enter the Americas did so by crossing the Beringia land bridge.
The debate over the exact route taken by the first humans to the Americas is ongoing and complex, but it is clear that the most likely path was by crossing the Beringia land bridge between East Asia and the so-called “New World”.
Archaeological and genetic evidence both consistently point to humans coming from East Asia first and slowly spreading out, both north and south, over the course of several thousand years, forming the many tribes and civilisations that would come to dominate the region.
Today, tens of millions of people in the Americas can trace their ancestry back to the first tentative steps taken by their ancestors over 13,500 years ago across the now-vanished Beringia land bridge.
