|View of a wall at the Cave of the Beasts.|
Amateur explorers stumbled across the cave, which includes 5,000 images painted or engraved into stone, in the vast, empty desert near Egypt's southwest border with Libya and Sudan.
Rudolph Kuper, a German archaeologist, said the detail depicted in the Cave of the Beasts indicate the site is at least 8,000 years old, likely the work of hunter-gatherers whose descendants may have been among the early settlers of the then-swampy and inhospitable Nile Valley.
The cave is 10 km from the Cave of the Swimmers romanticised in the film the English Patient, but with far more, and better preserved, images.
By studying the sandstone cave and other nearby sites, the archaeologists are trying to build a timeline to compare the culture and technologies of the peoples who inhabited the area.
"It is the most amazing cave ... in North Africa and Egypt," said Karin Kindermann, member of a German-led team that recently made a trip to the site 900 km southwest of Cairo.
"You take a piece of the puzzle and see where it could fit. This is an important piece," she said.
The Eastern Sahara, a region the size of Western Europe that extends from Egypt into Libya, Sudan and Chad, is the world's largest warm, dry desert.
Rainfall in the desert's centre averages less than two millimetres a year.
The region was once much less arid.
About 8500 BC, seasonal rainfall appeared in the region, creating a savannah and attracting hunter-gatherers.
By 5300 BC, the rains had stopped and human settlements receded to highland areas.
By 3500 BC, the settlements disappeared entirely.
Moving towards the Nile Valley
"After 3-4,000 years of savannah life environment in the Sahara, the desert returned and people were forced to move eastwards to the Nile Valley, contributing to the foundation of Egyptian civilisation, and southwards to the African continent," said Kuper, an expert at Germany's Heinrich Barth Institute.
The mass exodus corresponds with the rise of sedentary life along the Nile that later blossomed into Pharaonic civilisation that dominated the region for thousands of years and whose art, architecture and government helped shape Western culture.
"It was a movement, I think, step-by-step, because the desert didn't rush in. The rains would withdraw, then return, and so on. But step by step it became more dry, and people moved toward the Nile Valley or toward the south," Kuper said.
Kuper and his team are recording the geological, botanic and archaeological evidence around the cave, including stone tools and pottery, and will compare it to other sites in the Eastern Sahara region, adding new pieces to a prehistoric puzzle.
"It seems that the paintings of the Cave of the Beasts pre-date the introduction of domesticated animals. That means they predate 6000 BC," said Kuper, who led his first field trip to the cave in April 2009.
"That is what we dare to say."
The visible art work covers a surface 18 metres wide and six metres high.
In October, Kuper's team scanned the cave by laser to capture high-definition, three-dimensional images.
A test dig a few weeks ago during the team's third expedition to the sandstone cave uncovered yet more drawings that extend down 80 cms below the sand, Kindermann said.
"Now we have increasing evidence how rich the prehistoric culture in the Eastern Sahara was," Kuper said.