Recently, several studies have been published on the origin of the first Americans. The truth is that the goal is to know when and how the Homo sapiens came to the continent, but now it is fashionable because the results of various investigations have provoked debate. In fact, they have been based on different methods to analyze the origin of Americans, and the conclusions have been completely different.
However, it is not surprising that the results are different, since the investigations have had a different starting point and they may be compatible. To put it in some way, perhaps everyone is right.
Perhaps the research on the traces found in Mexico has been the one that has provoked the most debate and doubt. The case is that in central Mexico, traces of 40,000 years ago have been found. On a total of 269 steps, researchers have extracted data from the resident population at the site. According to researchers at Liverpool John Moores University, these steps are clearly made by the species Homo sapiens.
This affirmation, however, has generated a great stir among scientists. In fact, it disburses the existing theory. According to him, Homo sapiens arrived in America through northeastern Asia, passing by foot the frozen bridge between Siberia and Alaska. Some researchers have estimated that this occurred 14,000-15,000 years ago.
This corroborates it, for example, the genetic research carried out at the University of New Jersey. In addition, the number of households that arrived in the first migration has been calculated and, according to them, about 70. For the calculation, the researchers have compared the DNA of the North American Indians with the inhabitants of northeast Asia. Specifically, the number of modifications of nine parts of DNA has been analyzed, which has allowed us to know the size of the first migration.
For their part, researchers at the University of California have studied the expansion of Homo sapiens in America from a human tooth discovered in southern Alaska. The tooth is more than 10,000 years old, having extracted its DNA and comparing it with the genetic data of indigenous people throughout America. In view of the changes in DNA, they have discovered how the species spread over time.
In addition, they consider that the tooth owner's ancestors were Asian because their DNA is very similar to the DNA of a Chinese eastern ethnic population. It seems, therefore, that this research confirms that Homo sapiens arrived in America after the bridge between Siberia and Alaska.
However, the team that has investigated the Mexican footprints does not believe that this excludes their theory. In fact, they accept that this is a migration, but they believe there was an earlier migration. This is demonstrated by footprints and they propose that Homo sapiens arrived in America 40,000 years ago, by sea, crossing the Pacific by boat.