All modern humans may have originated from Botswana
*How wobble in Earth’s axis 130,000 years ago allowed our ancestors to leave the ‘Garden Of Eden’
All modern humans may have descended from people in what is now Botswana, according to scientists.Researchers think they have, for the first time, discovered the ‘cradle of humanity’ where the first modern humans evolved before spreading across the globe.
They are believed to have flourished in the prehistoric Makgadikgadi–Okavango wetland, just to the south of the Zambezi River.A study of Deoxy ribonucleic Acid (DNA)/genetic material records and migration patterns has proven, scientists say, that the genetic root of all modern humans comes from that region 200,000 years ago.
The wetland was a warm, lush green Garden of Eden in which early humans thrived before migrating when a wobble in the earth’s axis 130,000 years ago caused the climate to turn dry. And direct descendants of these pioneers can still be found living in the arid Kalahari desert today.
The Zambezi river pouring into Victoria Falls, near to the Khoe San people’s homeland in Botswana.“It has been clear for some time anatomically modern humans appeared in Africa roughly 200,000 years ago,” said the lead researcher, Professor Vanessa Hayes.“What has been long debated is the exact location of this emergence and subsequent dispersal of our earliest ancestors.”
Professor Hayes from Sydney University, studied the DNA of more than 1,200 living African people to pinpoint the origin of modern humanity. She took samples from people called the Khoe San, who live in rural Africa and who are known to be the most closely related to the original humans, and people genetically linked to them.
When humans first lived there, the Makgadikgadi–Okavango wetland, just to the south of the Zambezi River, was a thriving oasis perfect for the development of life. But the climate then changed, drying out the land and causing the wetland to become what is now a region of salt pans and desert, and forcing the early humans to migrate.
The area is now covered by the Makgadikgadi Pans National Park, which houses one of the largest salt pans in the world. For much of the year the only life that can survive on the pans is a thin layer of algae, but following the yearly rains it becomes an important habitat for migrating animals and birds, including one of Africa’s largest zebra populations.
The wet season also brings migratory birds such as geese, ducks and Great White Pelicans. The area is also home to one of southern Africa’s two breeding populations of Greater Flamingos.Her team could trace common ancestors of all the distinct groups back to the Makgadikgadi area of Botswana, which they have deemed the origin of man.
The findings, published in the journal Nature, add to existing geological and fossil evidence that prove Lake Makgadikgadi was home to early humans.In the past, scientists have suggested that smaller pockets of humans evolved in various places around Africa before spreading.
But Professor Hayes said the original humans evolved in the Makgadikgadi–Okavango wetland and remained there for a whopping 70,000 years. “There was a very large lake,” she said. “By the time modern humans arrived it was breaking up into smaller ones – creating a wetland.”And she claims ‘green corridors’ of vegetation grew out of the wetland, which developed from a lake twice the size of the 23,000-square-mile Lake Victoria in Tanzania and Uganda, allowing people to migrate north-east and south-west.Wetland is one of the healthiest ecosystems for sustaining life and would have been abundant enough for the human species to become established.
The climate then changed, drying out the land and causing the wetland to become what is now a region of salt pans and desert – this forced people to migrate.Professor Hayes said: “The first migrants ventured northeast, followed by a second wave of migrants who travelled southwest. A third population remained in the homeland until today. “In contrast to the northeasterly migrants, the southwesterly explorers appear to flourish, experiencing steady population growth.”
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