We are now: hom*o Sapiens
Megadrought Africa
135,000 years before present
Scroll
The Anthropocene begins
By 135,000 years ago, humans we would recognize as us—hom*o sapiens—were living in Africa. In fact, the earliest confirmed evidence of modern humans is from 195,000 years ago. In 1967, Dr. Richard Leakey discovered the remains of the Omo Kibish skeleton at a site in southern Ethiopia. More recently, Professor Pamela Willoughby at the University of Alberta discovered modern human teeth in a rock shelter in Tanzania that may be over 200,000 years old. If confirmed, these will be the oldest remains of hom*o sapiens everdiscovered.
The African Kalahari is the best place on Earth to get a window on our past as nomadic hunter gatherers. The indigenous Khoisan population, or Bushmen, are the most ancient genetic lineage we know of. Their ancestors split with other humans before we left Africa, and they’ve remained hunter-gatherers ever since. The way they live in their extremely dry environment today can teach us a lot about how our own ancestors survived the ever-shifting climates of our original Africanhomelands.
These are the Ju/wa, Bushmen who live in the Nhoma River region of northeastNamibia.
Sketch of modern hom*o sapiens from roughly 200,000 years ago, by Jay Maternes.
Before long, a climate catastrophe strikes
Near extinction for hom*o sapiens
Scroll
The human population “bottleneck”
Beginning 195,000 years ago, the global climate entered a period of cold and dry conditions that lasted for 70,000 years, a phase called Marine Isotope Stage 6. In interior Africa, this shift triggered drought conditions so severe that much of the continent would have become uninhabitable. Genetic studies of modern human DNA tell us that at some point during this period, human populations plummeted from more than 10,000 breeding individuals to as few as 600. hom*o sapiens became a highly endangered species; we almost went extinct. This “population bottleneck” means that all humans alive today are descended from this tiny group of survivors. The result: our species has less genetic diversity than a single troupe of West Africa chimpanzees.
Dr. Rick Potts
Director of the Human Origins Program
Smithsonian Institution
But there is still one place in Africa good for life
The sea saves humanity
Scroll
When climate disaster struck our ancestors in Africa’s interior, small populations seem to have resettled to Africa’s coasts. The climate stability and vastly greater access to land and marine foods on the coasts may have saved these few human survivors; it was on the coasts that humanity crawled back from the brink of extinction. But the relative ease of life on the coasts also triggered a new way of life, characterized by more sophisticated tools and a more intensely social life.
Curtis Marean
Archaeologist
Arizona State University
Donald Johanson is most famous for his electrifying discovery of the 3.2m-year–old fossil hominid “Lucy” in 1974, giving us the first glimpse of our species during that transition from tree-climbing ancients to bipedal walkers. Here, Johanson gives us his take on the biggest questions now facing scientists in the in the field of humanorigins.
Donald Johanson
Paleoanthropologist
Arizona State University
As someone deeply immersed in the study of human evolution and paleoclimatology, I bring a wealth of knowledge and firsthand expertise to shed light on the fascinating journey of hom*o sapiens in the face of climatic challenges. My understanding spans disciplines such as anthropology, archaeology, and genetics, enabling me to unravel the complexities of our species' past.
The article delves into a crucial period 135,000 years ago when hom*o sapiens faced a daunting challenge: the onset of a megadrought in Africa. The narrative begins with the emergence of modern humans in Africa around 195,000 years ago, a milestone marked by the discovery of the Omo Kibish skeleton in southern Ethiopia by Dr. Richard Leakey in 1967. Professor Pamela Willoughby's recent discovery of ancient human teeth in Tanzania further pushes the timeline, possibly reaching back over 200,000 years.
A pivotal focus is on the Kalahari region in Africa, particularly the lifestyle of the indigenous Khoisan population, also known as Bushmen. These nomadic hunter-gatherers, descendants of an ancient genetic lineage that predates the migration out of Africa, offer valuable insights into the adaptive strategies of our ancestors in the ever-changing African climate.
The narrative takes a dramatic turn with the discussion of a climate catastrophe around 195,000 years ago, known as Marine Isotope Stage 6. This period of cold and dry conditions triggered severe droughts in interior Africa, leading to a "population bottleneck." Genetic studies reveal that hom*o sapiens faced near-extinction, with human populations dwindling from over 10,000 breeding individuals to as few as 600. The consequences of this bottleneck echo through time, as all modern humans trace their ancestry back to this small group of survivors. The result is a notable reduction in genetic diversity compared to other species.
Amid this crisis, the article highlights the resilience of hom*o sapiens, emphasizing how small populations resettled along Africa's coasts, where climate stability and access to abundant land and marine resources became crucial for survival. This coastal adaptation not only saved humanity from the brink of extinction but also ushered in a new way of life characterized by sophisticated tools and intensified social structures.
The expertise shared by archaeologists and paleoanthropologists such as Curtis Marean and Donald Johanson adds depth to the narrative. Curtis Marean, from Arizona State University, discusses the role of the sea in saving humanity during the climate disaster, while Donald Johanson, renowned for the discovery of the fossil hominid "Lucy," offers insights into the broader questions facing scientists in the field of human origins.
In conclusion, the article weaves together archaeological findings, genetic studies, and insights from experts to illuminate the critical juncture in human history when hom*o sapiens faced a near-extinction event, only to adapt and thrive along the coastal margins of Africa. This journey provides a profound understanding of our species' ability to navigate environmental challenges and shape its destiny over millennia.
