The prehistoric site lay beneath the ruins of a medieval castle an hours drive from Tbilisi in the Republic of Georgia in a small town called Dmanisi. Archaeologists had first begun excavating the remains of a tenth century castle on the site in 1936. The castle was perched on a one thousand metres high rocky peak that dominated the small town of Dmanisi. In 1983, while examining an ancient garbage pit, an archaeologist uncovered what was identified as a tooth of a rhinoceros, a very strange find in a medieval castle in the Caucasus Mountains.
This led to further excavations and the following year stone tools were discovered then in 1999 the first of two fossil skulls were unearthed by the archaeologist David Lordkipanidze. To his very great surprise the skulls dated to around 1.8 million years BP. The fossils were composed of part of a young man’s skull and skullcap of a teen-age girl whose physical characteristics linked them to early Homo erectus though their brains were smaller, leading paleoanthropologists to compare them with Homo habilis and making them the oldest fossil evidence of the early man’s first migration out of Africa.
The fossil from Dmanisi included three skulls, three jaw fragments, and hundreds of stone tools and animal remains from the same strata. It also provided evidence that the environment and climate at that time had been similar to that of the modern East Africa savannah.
The discovery at Dmanisi added to evidence in Indonesia and China demonstrating that early man had left Africa hundreds of thousands of years earlier than had been previously thought and posed the question as to exactly when and why early humans left Africa.
Before the discoveries at Dmanisi, it had been supposed that the first humans to migrate out of Africa had large brains with advanced stone tools, such as hand axes, allowing them to butcher large animal carcasses. However, the discovery of Homo habilis at Dmanisi with his smaller brain and the stone tools found at the site; simple choppers and scrapers, similar to the Oldowan set found in the Olduvai Gorge, Tanzania, showed that early humans with elementary technology had expanded out of Africa before erectus, that was unless they had forgotten more advanced tool making techniques.
The question that was asked again and again was, why do people migrate? The answer was always because of food and since the availability of food was linked to climatic variations. Borneensis and his ancestors lived for almost two million years in a very stable ecological and plentiful niche, which was probably why he survived so long, plenty of food and little competition, in other words Borneo was a primitive Garden of Eden.
Many scientists had supposed that the first human to have left Africa needed to be equipped like modern hunter-gatherers. The reality was that early man had moved across a familiar savannah like environment in search of food and game, not according to a intentional form of immigration, conceived by men with more developed brains and tools. After all the great apes and monkeys had colonised the planet over millions of years without the least tools and without bipedal adaption.
When and where Homo erectus emerged in Africa was not known with any exactitude, but evidence shows his presence starting about two and a half million years ago. Very soon after he appeared in regions outside of Africa, which today are Georgia, China, Indonesia and Europe, evolving about half a million years ago into different forms, such as Neanderthals in the Western part of the Eurasian continent and archaic humans in China and Indonesia. Discoveries in the Middle Awash in Ethiopia, a region that has yielded the world’s longest record of fossil hominoid remains spanning five million years, showed that the African branch of erectus had evolved into Homo sapiens.
Ethiopia was a pivotal region between Africa and the Eurasian continent, where due to cyclic climatic change over the last two million years the landscape swung between desert and savannah and where fossils showed that the fauna was not very different to that of the present African savannah. The movement of early humans out of Africa no doubt occurred as they simply extended their territory, moving across a familiar savannah like environment up and down the Red Sea coast into Israel and then on to Eurasia as conditions permitted.
Homo erectus is considered by most paleoanthropologists to be a single species with a wide distribution across Asia, Europe and Africa. Thus it was logical to imagine that a cross flow of genes must have occurred between compatible populations of hunter gatherers that were constantly on the move in their search for food and game across the Eurasian and African continents over a period of about one million years.
Western Europe, Eastern China and Indonesia were all extremities of the Eurasian continent, in other words dead ends, which had always been sites where vestige populations survived. Fossils from the site of Ngandong in Java clearly demonstrated that erectus continued to live in that extreme point of the Eurasian landmass until just 27,000 years ago. The Ngandong crania were considered as Homo erectus, though having certain variations in comparison to the earlier specimens found in Java or in China. Some scientists proposed that Ngandong man lay between the earlier Homo erectus of Java and modern Australians, with the suggestion of gene flow between Asian Homo erectus and Homo sapiens.