Between 160,000 and 135,000 years ago, human beings set off on their long walk to the future. Some believe the journey began in southern Africa, others in eastern Africa. The jury of anthropologists is still out.
Millennia after they set off and at some imprecise date between 135,000 and 110,000 years ago, people travelled along the banks of the river we now call the Nile through a green and fertile Sahara to the Levant. It must have been a perilous journey. In any case that branch of humanity eventually died out some 90,000 years ago when the region turned into arid desert.
Much later, between 90,000 and 85,000 years ago, people crossed the mouth of the Red Sea and trekked as beachcombers along the southern coast of the Arabian Peninsula towards India. Over the next 20,000 years, they followed the coast towards Indonesia, which at that time was still attached to Asia. Still hugging the coast they moved on to Borneo and South China.
Some 74,000 years ago, a catastrophic volcanic eruption of Mt. Toba in Sumatra led to an ice age that drastically reduced the local population. When numbers began to recover, between 73,000 and 65,000 years ago, people returned to India and began to cross over from Timor into Australia and from Borneo into New Guinea. The northern regions of Asia were uninhabitable because of intense cold.
Between 65,000 and 52,000 years ago, global warming allowed groups of people who had remained in Africa to move northward up the Fertile Crescent and repopulate the Levant. From there, some 50,000 years ago, they crossed into Europe via the Bosporus. By 25,000 years ago people had reached the Arctic Circle and Northeast Asia, crossing the Bering land bridge into North America some 22,000 years ago.
The ice age that followed – 22,000 to 19,000 years ago – left pockets of survivors in northern Europe, Asia, and North America who later, between 19,000 and 15,000 years ago, began moving south towards South America.
Finally, between 15,000 and 12,500 years ago, with the world’s climate improving all the time, people followed the retreating ice northward to become Inuit, Aleuts, and Na-Dene speakers and Britain and Scandinavia were recolonized. The end of this ice age heralded the dawn of agriculture.
The time span is almost inconceivable. Now, scientists working in southern China, have discovered teeth belonging to modern humans that date back at least 80,000 years, setting the calendar back more than 20,000 years. All the fossils were found beneath a calcite floor, which had sealed them in, so the teeth have to be older than that layer. Using uranium-thorium dating, stalagmites on the floor were found to be 80,000 years old. The human teeth may predate them by a further 45,000 years.
Who were these people? How did they live? Did they have language? Mere shadows in the caves of time, we cannot know. Over 130,000 years of human history are missing and their stories will never be known. Our ancestors, they could not foresee that they would be the objects of scientific study – or that hundreds of thousands of their descendants would demonstrate the same resilience and endurance as they, too, became migrants in search of a better life.