A recent study used radioactive carbon dates to confirm that the indigenous population in the United States reached its peak at around 1150 AD, then decreased and settled by around 1450 AD, then decreased after the arrival of Europeans.
The decrease in the original population of the Americas after the European invasion is widely known, but unless it is clearly understood, the decrease in the population before the European invasion.
Researchers have long sought to estimate the size of the indigenous population in North America before European colonialism in order to assess the impact of colonialism on the indigenous population on the continent.
According to these the study It was published in February in the Journal of the National Academy of Sciences (BNAE), the Europeans were lucky because they colonized North America and other regions of the Western half of the world at this time specifically, and perhaps if they had reached a few hundred years, they could have faced a greater number of native populations in political conditions and a community cohesion, and this population could have reacted strongly in the strong way of the native population under political conditions and better community cohesions, and these populations could have responded strongly in the strong way of the population and the native population under political conditions and better community cohesion, and this population could have responded strongly to the strong and the reception of the population strongly towards the manner strongly towards the manner and the population the European invasion, and if this North America would be completely different.

Striped carbon secret
The study used to achieve these results a database that includes more than 60,000 radioactive carbon stories found in the Canadian Canadian Radio-Carbon Database (Card) Canadian.
In a statement in Al -jazeera net via E -Mail, Dr. Andrew Candel, the archaeologist of the Topping University, said that the history of radioactive carbon is used in anthropological studies, because it allows scientists to determine the age of human activities that have occurred in the past.
Candel adds that they use organic residues such as bone, coal, shells and other remains discovered in archaeological excavations, then they analyze them using the method of radioactive carbon history, which is also called carbon 14, then they send discoveries to the laboratory so that they can determine the somewhat precise age of these materials, and then they can use these results to understand the past behavior.
The history of carbon radio or carbon history was developed for the first time in the late 1940s at the University of Chicago by a team led by the chemistry teacher and Williad Libby, who then received the Nobel Prize for this work.
This scientific method can determine the age of organic matter, which is around 60 thousand years old, and this method depends on the fact that living organisms such as trees, plants, human beings and animals absorb carbon 14 and maintain it in their tissues.
And when these organizations die, carbon 14 begins to transform into other atoms over time, and scientists can estimate the duration of the body by calculating the rest of the carbon atoms 14.

Why has their number decreased?
According to the study, the decrease in the population of origin in North America before the European invasion was not an abnormal example in the history of the world, because the number of all populations around the world is vulnerable to the rise and decline, whether due to climate change or migration, and population increases can occur due to technological and social innovations.
The decrease in the population can be due to infectious diseases.
In a statement to the island, Dr. Spencer Bilton, the archaeologist of the University of Wyoming, United States, said that diseases, wars and climate change are probably the reasons for the decrease in the number of Aboriginal population in North America before the European invasion, or perhaps a mixture of these combined reasons.
Is the history of radioactive carbon the most precise way?
But it Seems, As It Seems More Research, To Confim the Results, As the Radioactive Carbon History can be sometimes Biased for Several Reasons, Including pollution or the bias of the Researcher or Deep Burial of Archaeological Sites, and Other Reasons, Scientificially can be scientific overcomed Problems, and the carbon 14 History can be replaced by other history methods, such as tree history, archaeological history and archaeological pieces and archaeological pieces information on history.
In his declaration in Al -jazeera Net, Bilton says that archaeologists in North America have used radioactive carbon dates to estimate the old number of human populations for a long time, but this practice has become more complicated in the past 15 years.
Archaeologists use other methods other than carbon radioactive history to deduce the size of the population, starting with the use of traditional means such as old sites or housing or artifacts to the use of emerging applications such as the 1960s feces, which are molecules of organic resistance resulting from human waste that remains in sediments for hundreds of years, change of population.