DNA and Human Migration
Table of Contents
The human genome is identical in people up to nearly 99.9 percent all over the world, and the remaining difference of 0.1percent can be accorded to DNA, which is unique in every human being. It gives a characteristic eye color or rarely a mutation that is passed on to a person’s descendants. Thus, on the basis of these characteristics, DNA makes it possible to trace back a person’s origin. An aspect that should be kept in mind when making this kind of research is that a mtDNA can only be transferred from a woman to child, and a Y chromosome transfers from father to son. Therefore, by examining the mtDNA and Y chromosomes due to the similarities of mutations, the lineage of a person has been made traceable. Therefore, the history of Human Migration is revealed by the chain of DNA that is responsible for human genes. Research of this domain is further progressed by the latest machinery used to assess the migration dynamics by scanning for matches in the genes of people living in different parts of the globe. The findings determine the human lineage and ancestry despite geographic differences. The most up-to-date gene-scanning tools provide high-resolution images that help to detect the history of human migration etched into human DNA.
According to Shreeve (2006), the women’s mtDNA from different parts of the world has been analyzed and compared. The results showed that the genome in African female population is twice more diverse than that of women from other parts of the world. An interesting fact is that the study has also provided evidence for the religious belief that all humanity is the offspring of Eve. At the same time, the San people of Southern Africa, Biaka Pygmies of central Africa and some East African tribes have been found to carry the ancestral DNA genome. It gave way to the assumption that about 50,000 to 70,000 years ao, a group of about thousand people from Africa could have migrated to Asia. The cognitive skills and tools used by these people corresponded to those used in the settlements in Asia, one about Middle East and Sinai Peninsula north of Levant and another one – through Himalayas, reaching eventually into Japan, China and Siberia.
Australians find their ancestral roots from a man buried by the side of Lake Mungo, whose remains suggest the period of around 45,000 years. However, no further traces of people are found further up to 8,000 miles along Africa to Australia. The remains must have vanished owing to the rising sea levels after the ice age had subdued.
DNA of current Eurasians is similar to that of Indian people; therefore, there is a possibility that an inland migration must have occurred from Asia to Europe around 30,000 to 40,000 years ago. In addition, about 40,000 years ago, human civilization advanced to Neanderthal, a suggestion based on the artifacts found in a cave in France.
The Americans trace their origins from Siberians 20,000 to 15,000 years back. Sea levels were low enough for Siberia to have a land connection with Alaska, a migration must have ensued. However, the land in this region must have been ice covered and caused the immigrants to move towards the west coast. At the same time, a 9,500 years old skull found in America, Washington DC that is called the Kennewick man is considered as evidence of the lineage of Americans to Northern Europe (Shreeve 2006).
It should be noted that these facts have been supported by other research made from time to time. For example, a research undertaken at Stanford and the University of Michigan developed the statistics to the following conclusions:
– Human tree was initially rooted in Africa. It later branched out to the Middle East, Europe, South Asia, East Asia, Australia and lastly to the Americas.
– The differences found due to the genetic tests mark that there are hardly any prominent differences among the genomes of a particular ethnic group.
– The longer a group remained in one geographic area, the more it is found to have ceased the regional genetic markers.
– Distinctive genome patterns are also possible in a single group along with a portion of ethnic genes markers (Russell 2008).
Another Research on human migration in eastern Asia conducted a close examination of hominid fossils in eastern Asia. A significant gap was revealed between H. S. Sapiens and H. Sapiens, with respect to time continuity. All the H. S. Sapiens fossils found so far are approximately less than 50,000 years (with most being 10,000–30,000 years old) while the H. Sapiens fossils are at least 100,000 years old. Another important factor of human migration is an observation that no hominid fossils that can be dated 50,000-100,000 back are found for the moment. Therefore, the following results were derived from this research:
- The first human migration in the south of Eastern Asia took place even earlier than 60,000 years ago.
- A northward migration was followed by glaciers in that area.
- Prior hominids living in eastern Asia had disappeared before or during the last Ice Age.
- The African human descent with dominating H8 and H6 haplotypes migrated to eastern Asia.
- Humans with same genomes later travelled to the north inhabiting northern China and then Siberia (Genet 1999).
According to the data provided by Shreeve (2006), the following conclusions can be made:
- All males migrating from Africa carried a marker M168, which is found in non-Africans only (Non Africans).
- M9, a marker inherent in Europeans had its origin in Central Asia or Middle East. (Eurasians).
- M3, a general marker in Americans can be traced to Asians (Amerindian).