Africa's Oldest Human DNA Unravel Unravel Complexities of Long-Distance Migration by Ancient Humans

Africa's oldest human DNA revealed why our ancient African ancestors 20,000 years ago stopped traveling long distances to search for their potential mate which started 50,000 years ago. Instead, several DNA samples showed long-distance mate seekers just stayed within their region.

The excavation of the oldest DNA samples from various ancient human groups in Africa indicates that either socio-cultural or natural phenomena may be the cause behind the sudden shift in migration patterns relating to population reproduction.

A shift from continental to regional travel for copulation, the new discovery helped archaeologists to explain the reason behind the appearance of various toolmaking objects, stones, and other cultural behaviors across Africa starting 50,000 years ago.

Shift in Migration

(Photo : Gianluigi Guercia/AFP via Getty Images)

In a new study published in the journal Nature on Wednesday, Feb. 23, archaeologists explored the probable causes of why our ancient African ancestors stopped long-distance mating around 20,000 years ago, a practice that started 30,000 years earlier.

The study highlighted the change of pattern among ancient Africans from traveling long distances across Africa into staying only within their respective regions of what is now comprised of North Africa and West Africa, East Africa, and sub-Saharan Africa.

Based on the study, long-distance mate seekers, including hunter-gatherers and herders, eventually refrained from traveling outside their home regions and shifted to finding partners for copulation within the confinements of their regional homes.

Also read: Oldest Human Skull in Laos Sheds Light on Earliest Migration from Africa

Potential Cultural and Climate Shift Factors

According to Science News, the study's co-author Jessica Thompson, a bioarcheologist at Yale University, stated there may be both cultural or climate-related factors on the reasons why ancient Africans preferred to stay home rather than continue their long-trekked journeys.

Thompson reportedly claimed that the people may have stayed home due to the last ice age at that time since the climate shift might have resulted in the decline of animals and plants essential for survival during long-distance travel.

In terms of cultural aspects, Thompson postulated the ancient long-distance mate seekers preferred to choose a partner within their own social and cultural circles-with whom they have a variety of similarities. Meanwhile, migrants with a different background from far regions were less selected.

Archaeological Excavation and DNA Sampling

Thompson and the archeologists from the study were able to determine the shift of pattern concerning long-distance mating through the collection of Africa's oldest human DNA of Homo sapiens-who have inhabited the African continent during the Stone Age, according to the study.

They collected ancient DNA samples from several ancient individuals in the continent who lived approximately between 18,000 and 5,000 years ago. The excavation also led to the possibility that an unknown human population in Africa may also have contributed to today's modern Africans.

The archaeologists were able to create a genetic map that the ancient DNA belong to three present African groups, including the Mbuti hunter-gatherers in central Africa, Dinka farmers and herders in northeastern Africa, and San hunter-gatherers from southern Africa, as per Science News.

During a drastic climate change 300,000 years ago, H. sapiens evolved and thrived in Africa-where they developed various skills in the areas of toolmaking, hunting, and socio-cultural interactions, according to the Smithsonian National Museum of Natural History.

Related article: Egypt May be the Key to Human Migration Out of Africa