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Theories About The First Americans
Transcript of Theories About The First Americans
By: Zhiyong, Zhan, Seongha
Land Bridge Theory
It is believed that 12,000 years ago, there was a bridge connecting Asia and America, allowing humans and animals to move from Asia to America.
This theory was first proposed by José de Acosta in 1590, but it was only accepted since 1930s
Even this theory is widely accepted, there are still evidence that humans lived in America before that.
Some evidence that proves this theory to not be true are:
There was civilization 12,500 years ago in Chile, 10,000 miles away from Alaska.
There are also artifacts from 24,000 years ago, but the first americans arrived 12,000 years ago.
Some artifacts in Pennsylvania that are as old as 19.000 years old, 7,000 years before the first americans arrived.
Pacific Coastal Theory
Transportation by water was developed 40,000 years ago. People are still finding evidence of existence Americans 13,000 years ago. The scientists are now, looking carefully for artifacts that had supported the land route theory.
Knut Fladmark is said, in 1970s, that the first americans came from Asia to America via watercraft. He knew that it was hard to find evidence to prove that this theory is true, but he wanted to find out if it was true or not. Fladmark said “If people had a reason to keep moving, they could have traversed both continents in 100 years”. He went to travel by boat and he believed that that land should have been inhabited for 14,000-15,000 years ago.
A possible evidence is that Australia and Japan used boats as long as 40.000 years ago
It is hard to find evidence to prove this theory because the water level was lower a few thousand years ago, so the sites are underwater.
Atlantic Coastal Theory
The Atlantic Coastal Theory is the theory that scientists came up thinking that the first americans might be from Europe, traveling through the Atlantic Ocean using boats.
The new evidence scientists found made another theory. Archeologists found a skull in south eastern Brazil of an African woman. So scientists thought that people might have traveled directly from Africa to America But also, scientists think that they could have gone through Asia and through the land bridge. So, this evidence proves that America was a diverse land. This means that peoples came from many different places of the world and it all relates to each other. The weapons and tools were similar to these sites so scientists dubbed them the ´Clovis´ people.
The problem on proving this theory is that besides there are similar spears in Europe that are found in sites in America, there are no other evidences
What we believe
We believe on the Land Bridge theory because is the most reasonable comparing to other ones, especially Atlantic Coastal Theory because boats from thousands of year ago crossing a whole ocean is not really convincing and the Pacific Coastal Theory doesn't have quite enough evidence to prove it.
taken from: http://wps.ablongman.com/wps/media/objects/1483/1518969/DIVI001.jpg
taken from: http://www.fourdir.com/workbook5_toc_graphic.jpg
Taken From: http://www.sfu.ca/archaeology-old/dept/fac_bio/fladmark/index.htm
Taken From: http://www.nature.com/news/ancient-migration-coming-to-america-1.10562
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