The Arabian Peninsula forms a bridge between Africa and Asia – our ancestors also knew how to use this connection route. However, it is unclear when Homo sapiens reached Arabia. Now researchers have discovered human footprints that are 120,000 years old in an old sea bed in Saudi Arabia – they are the oldest evidence of our ancestors in this region to date. In addition to human traces, hundreds of prints of animals such as elephants, camels and horses are also preserved in the sediment. They prove that this now dry desert region was rich in water and fertile enough to feed humans and animals.
The Arabian Peninsula is today a rather inhospitable region characterized by drought and deserts. This is one of the reasons why their early history has so far hardly been researched. There are now numerous fossil discoveries that prove that Homo sapiens must have reached the Levant from Africa more than 130,000 years ago. For a long time it remained unclear whether our ancestors also moved to Asia via Arabia and whether this region was at all friendly enough at that time. However, there is now sufficient evidence that the Arabian Peninsula went through several phases with a mild, humid climate between 120,000 and 80,000 years ago. “There have been times in the past when deserts turned into vast grasslands with freshwater lakes and rivers,” explains Richard Clark-Wilson of Royal Holloway University. “During these periods of climatic upswing, human and animal populations also penetrated into the interior of the peninsula, as the archaeological and fossil records show.” The oldest evidence of this was around 100,000 years old.
Footprints in the prehistoric lake bed
But now there are older traces – in the truest sense of the word. Clark-Wilson, Mathew Stewart from the Max Planck Institute for Chemical Ecology in Jena and their colleagues discovered hundreds of fossilized footprints in the Nefud Desert in Saudi Arabia, dating from around 120,000 years ago. Among the approximately 370 prints there are numerous traces of large herbivores such as elephants, camels, horses and antelopes. “We immediately saw the potential of these finds,” says Stewart. “Footprints are a unique form of fossil evidence in that they provide snapshots of the past that typically only cover a few hours or days, a high resolution that we usually cannot get from other records.” Finding numerous footprints in one place and more Findings in the lake’s sediments suggest that the animals gathered around the lake when prolonged drought led to a decreasing water supply.
Among the many animal tracks, the researchers also discovered seven human prints. Given their shape and size, and their dating, they conclude that it must be traces of our ancestors. “There is evidence that Neanderthals only moved to the region after the last interglacial period and with the return of cooler conditions,” says Stewart. “The footprints we found therefore most likely come from members of our species, Homo sapiens.” Four of the human footprints are close together on the southwestern edge of the primeval lake. “Given their alignment, their distances from one another, and their different sizes, they probably belonged to two or three individuals who walked this way together,” the scientists explain.
Earliest evidence of human presence
These footprints are the earliest dated evidence of a human presence in this part of the world. “The presence of large animals such as elephants and hippos, as well as open grasslands and large water resources, could have made northern Arabia a particularly attractive place for people who moved between Africa and Eurasia,” says co-author Michael Petraglia from Max Planck -Institute for Human History. What these people did at this lake back then, whether they scooped water, looked for food or just rested, is unclear. “We know that people visited the lake, but the lack of stone tools or finds indicating the use of animal carcasses suggest that their visit to the lake must have been brief,” says Stewart.
Overall, these findings suggest that the Arabian Peninsula and its north were both visited and used by humans during the last interglacial period. At the same time, the traces confirm that Homo sapiens had left Africa 120,000 years ago and was present in both the Levant and Arabia.
Source: Mathew Stewart (Max Planck Institute for Chemical Ecology, Jena) et al., Science Advances, doi: 10.1126 / sciadv.aba8940