HUMAN MIGRATION Mitochondrial DNA, which is only passed from mothers to their children, is used to determine the migratory patterns of early humans, which was modified by the fact that the continents were a bit more accessible to one another than they currently are. Genetics has helped the investigation of migration patterns. The genus Homo has migrated out of Africa a minimum of three separate times. The migration patterns are believed to be related to changes in the climate. Human artifacts have been found near New Delhi that date from 2.6 million years ago. This is earlier than it was once believed. Chinese archaeological digs have found human tools from about 2.5 million years ago. The area of Ethiopia in Africa is believed to be the origin of the X and Y chromosomes of the first human man and woman. Modern humans are believed to have exited Africa about 55,000 years ago, even though others left earlier than that. Genetic studies have identified Mitochondrial Eve and Y-chromosomal Adam. These were the progenitor humans that first gave rise to our modern human species. The theory is called Out of Africa”, which has also been supported by archaeological findings, such as the finding of Lucy, an example of an australopithecine from 3.2 million years ago in the 1960s in Ethiopia. There was some mixing between Neanderthals and Denisovan species and, as mentioned, all humans have Neanderthal genes—about 2 to 4 percent of the total genome. Some modern humans living near Fiji and New Guinea have Denisovan alleles as well. This does not complicate the idea that we came out of Africa but suggests it did not just happen once. Denisovan genes have been found in Tibetan populations as well. The most current dispersal theory indicates that humans dispersed along coastal regions to an area around Yemen around 70,000 years ago, populating Oceania and Southeast Asia. They were believed to use mainly marine resources. A later group traveled through the Persian Gulf to the Middle East, while some populated Eurasia. Rising sea waters likely destroyed most of the evidence of the first group of migrants. There is a single migration lineage called L3 that gave rise to all people who are not African.
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