Adaptation to coastal environments and the exploitation of marine resources are considered crucial for the survival of early humans and their successful out-of-Africa expansion during the early Late Pleistocene (126000 to approximately 60000 years ago).
In view of its strategic geographic position along the African side of the Red Sea, Eritrea (with about 1300km of coastline) represents an ideal place to look for prehistoric sites associated with human dispersals out of Africa.
Subsequent to the research carried out in the year 2000, several field projects were conducted along the Gulf of Zula region. These intensive field works further enriched the initial evidence known from the site of Abdur. At this time several prominent sites that correspond to the Middle and Late Stone Age sites (Asfet, Gelealo-NortherWest, Misse-East) have been identified at a distance not far from the site of Abdur. Archaeological studies from these sites demonstrated that the region was a refugium and dispersal corridor of Modern Humans during the Late Pleistocene times.
In the year of 2000, an article published on Nature demonstrated the earliest well-dated evidence of human occupation in coastal marine environments. This was realized from evidence of stone tools, fossil corals and oyster shells from the Eritrean coastal site of Abdur at the Northern Red Sea Region. The site is found halfway between Irafaile and Gelàalo areas alongside the Massaw– Assab road. Abdur is of essence in understanding the evolutionary history and dispersals of Modern Humans. British paleontologist, evolutionary biologist and ex-senior editor of the scientific journal of Nature, Henry Ernest Gee, once reported findings from this site, referring to the first publication by Robert C. Walter and his colleagues in the year 2000 (See, Walter, R.C. et al., Early human occupation of the Red Sea coast of Eritrea during the last interglacial. Nature 405, 65 – 69 2000). Henry Gee described this scenario as “the first things that humans did after they evolved was to head for the beach”. Following is the report of Henry Gee published on “Nature” on the 4th of May, 2000.
Stone tools mixed in with fossil corals and oyster shells are a sign that the human romance with the seaside is as old as the species itself. Robert C. Walter of the Centro de Investigación Cientifica de Educación Superior (CICESE) in Ensenada, Mexico, and colleagues have found stone tools laid down 125,000 years ago on what were once beaches and coral reefs on the Red Sea coast of Eritrea in East Africa. This work has been published in Nature.
Although only tools have been discovered ? not the toolmakers themselves, let alone any beach towels or bottles of suntan lotion ? the researchers claim that the discovery signals a sea change in human behaviour. This change could have marked the beginning of the human love affair with seafood, boats and all matters maritime.
The first fossils of recognizably modern humans come from the interior of East Africa and are dated to around 130,000 years ago ? a period of intense drought in Africa that coincided with an Ice Age in Europe. Walter’s group thinks that early modern Homo Sapiens might have sought refuge from the aridity of the African hinterland in the milder climates of the coast.
Some 125,000 years ago, the world was experiencing an ‘interglacial’ ? one of the warm, wet spells that punctuate longer periods of drought (and, in the North, extreme cold). It was so warm that hippopotami wallowed in rivers as far north as Yorkshire in England, and early humans started to migrate from their African homeland.
Meltwater from ice-sheets swelled the world’s oceans, driving global sea levels to heights not seen since. ‘Fossil’ beaches from that warm spell can be found today, as ‘terraces’ standing several meters above present-day beaches.
The first member of the human family definitely known to have left Africa was Homo erectus, perhaps as long as two million years ago. Homo erectus penetrated the whole of tropical and temperate Eurasia, evolving into distinct local forms such as Neanderthals in Europe and western Asia.
Modern humans (Homo Sapiens) originated in Africa and, according to the most popular model of human evolution, migrated from Africa between 200,000 and 100,000 years ago, replacing the earlier, indigenous hominid species. It is thought that the migration route, out of Africa, of modern humans would have been inland, through the Sinai Peninsula and into the Middle East.
But recent work has suggested that human beings might have taken a coastal route, through the Red Sea, southern Arabia and into Asia as far as Indonesia ? a theory that is substantiated by this latest report from Eritrea.
Researchers will now be keen to head for ancient beaches to track the metaphorical footprints left by the earliest members of our species. There is, however, a catch. Because the current global sea level is almost as high as it was 125,000 years ago, virtually all the beaches of interest are now submerged, barring a few in Arabia, India and other parts of southern Asia. Migration along the beach could have provided a way for modern humans to get around the world quickly. Only later did they head inland, perhaps along estuaries and river valleys. This might have led to the extinction of indigenous forms of humanity still clinging on in the hinterland. Remnants of Homo erectus, for instance, lived in the Javan interior until 100,000 years ago. The situation in Europe is complicated by the geography of glaciation ? and the fact that modern humans did not penetrate that chilly continent until around 40,000 years ago, dislodging the highly successful Neanderthal residents.