The human origin story is far more complex than we’ve known.
A new study promises to lift the veil on some of the greatest mysteries concerning the origins of modern humans: Where we all originated from.
A new study claims that all modern humans most like are descendants from people that lived in modern-day Botswana.
Experts have revealed that they’ve managed, for the first time ever, to find the “real” cradle of humanity where the very first modern human evolved, before making their way across the globe, eventually populating the entire planet.
According to the new study, the cradle of humanity can be traced back to the prehistoric Makgadikgadi–Okavango wetland, located to the south of the Zambezi River. This is according to the study of DNA records and migration patterns which have shown that the genetic root from al modern humans originated from that region around 200,000 years ago.
The prehistoric Makgadikgadi–Okavango delta was once a lush green “Garden of Eden” where early humans thrived and developed before making their way to different parts of the continent and the world as the climate of the region changed from green to dry land.
Scientists are so confident about their discovery that they say that the direct descendants of early humans can still be found inhabiting the arid Kalahari Desert today.
The researchers studied L0 mitochondrial DNA which humans inhabit from their mother.
“It has been clear for some time that anatomically modern humans appeared in Africa roughly 200 thousand years ago. What has been long debated is the exact location of this emergence and subsequent dispersal of our earliest ancestors,” revealed study lead Professor Vanessa Hayes from the Garvan Institute of Medical Research and University of Sydney.
“Mitochondrial DNA acts as a time capsule of our ancestral mothers, accumulating changes slowly over generations. Comparing the complete DNA code, or mitogenome, from different individuals, provides information on how closely they are related.”
Scientists studied the DNA of around 1,200 people inhabiting parts of Arica in order to pinpoint the exact place of origin. The researchers took DNA samples from the Khoisan people who inhabit rural Africa, and who are believed to be the most closely related to the early humans and people genetically similar to them.
This allowed scientists to trace their common ancestor and that of all the distant groups of people to the Makgadikgadi region, which they have dubbed the cradle of humanity. In addition to DNA studies, a plethora of different geological and fossil discoveries suggest how Makgadikgadi was indeed the home of early humans.
The new discovery published in the Journal Nature contradicts previous theories which have suggested that smaller groups of early humans evolved and developed in different parts of Africa before making their way into the world.
But despite this theory, the researchers say that the ancestors of modern humans arose in the Makgadikgadi–Okavango wetland and remained there for around 70,000 years when the climate of the region changed.
The wetlands of the region are key in the development of early humans say experts, since wetlands are one of the healthiest ecosystems that allow life to flourish, providing enough resources for the human species to become established.
As the climate changed turning the wetland to an arid desert landscape, early humans were forced to migrate to other more fertile parts.
The scientists revealed that early humans traveled to different parts of the continent. The very first migration took humans to the northeast. The second group of people is believed to have traveled to the southwest, while the third group of early humans remained in the region until and their ancestors continue inhabiting the lands today.
“In contrast to the northeasterly migrants, the southwesterly explorers appear to flourish, experiencing steady population growth,” revealed Professor Hayes whose study argues that the success of the southwestern migration was most likely due to a rapid adaptation to marine foraging.
The success of this migratory group is supported by archaeological evidence along the southern tip of the African continent.
The researchers also discovered the likely cause of what caused early humans to migrate. According to the co-author of the study Axel Timmermann, Director of the IBS Center for Climate Physics at Pusan National University, the wobble of Earth’s axis changes summer solar radiation in the Southern Hemisphere which leads to periodic shifts in the rainfall across the entire southern part of Africa.
“These shifts in climate would have opened green, vegetated corridors, first 130 thousand years ago to the northeast, and then around 110 thousand years ago to the southwest, allowing our earliest ancestors to migrate away from the homeland for the first time,” revealed Professor Timmermann.
The people who decided to remain in their original location eventually adapted to the drying lands of the region.
The new study combines genetics, geology, and climatic physics to rewrite our earliest human history.