Who built the Egyptian colossus and why did they abruptly stop before it was finished? New research reveals a changing climate my have shaped the fate of the statue.
No human endeavour has sparked such controversy as the 4,500-year-old statue that lies a mere stroll from the great pyramids of Giza in Egypt. A huge, ancient lion sporting a human head seemingly guards over something on the rocky, desert plateau - but over what, no one can say.
For thousands of years the Sphinx has teased visitors with its secrets - its name, its purpose, its history. And it was a twisting path that led an American archaeologist, Mark Lehner, to solve the riddles of the Sphinx and become one of the world's leading Egyptologists. Back in 1971, Lehner was just a typical bored college student at the University of North Dakota, who was "looking for something, a meaningful involvement."
He became an enthusiast for the late clairvoyant Edgar Cayce - who, in a trance, had seen refugees from the lost city of Atlantis bury their secrets in a hall of records under the Sphinx. In an attempt to ease the restlessness of his youth, Lehner dropped out of school and sought out Cayce's son, Hugh Lynn, the head of a holistic medicine and paranormal research foundation his father had started in Virginia.
When the foundation sponsored a group tour of the Giza plateau, on the western outskirts of Cairo, Lehner tagged along. "It was hot and dusty and not very majestic," he remembers. He also failed to see any evidence of the fabled library of Atlantis.
Still, he returned to Egypt, finishing his undergraduate education at the American University in Cairo. He soon grew sceptical about Cayce's visions, but instead became hooked on Egyptology.
He developed an ambitious plan to map the entire Sphinx; he was granted a bit of research money and set up a tiny office between the Sphinx's colossal paws. For five years, he subsisted on Nescafé and cheese sandwiches while he examined the statue. He remembers "climbing all over the Sphinx like the Lilliputians on Gulliver, and mapping it stone by stone."
The result was a uniquely detailed picture of the statue's worn, patched surface, which had been subjected to at least five restoration efforts since 1400 BC. The project earned him a doctorate in Egyptology from Yale University.
In 1977, he joined Stanford Research Institute scientists in using state-of-the-art remote-sensing equipment to analyse the bedrock under the Sphinx. They found only the cracks and fissures expected. Working closely with a young Egyptian archaeologist named Zahi Hawass, Lehner also explored and mapped a passage in the Sphinx's rump, concluding that treasure hunters had likely dug it after the statue was built.
Recognised today as one of the world's leading Sphinx authorities, Lehner has conducted field research at Giza during most of the 37 years since his first visit. (Hawass, his friend and frequent collaborator, is now the secretary general of the Egyptian Supreme Council of Antiquities and controls access to the Sphinx, the pyramids and other government-owned sites and artefacts.)
He has helped confirm what others had speculated - that some parts of the Giza complex, the Sphinx included, make up a vast sacred machine designed to harness the power of the Sun to sustain the Earthly and divine order. And it's curious, in light of his early wanderings, that he finally did discover a Lost City.
The Sphinx was not assembled piece by piece, but was carved from a single mass of limestone exposed when workers dug a horseshoe-shaped quarry in the Giza plateau. Approximately 20 m tall and 75 m long, it is one of the largest and oldest monolithic statues in the world.
The face, though better preserved than most of the statue, has been battered by centuries of weathering and vandalism. In 1402, an Arab historian reported that a Sufi zealot had disfigured it "to remedy some religious errors."
Yet there are clues to what the face looked like in its prime. Archaeological excavations in the early 19th century found pieces of its carved stone beard and a royal cobra emblem from its headdress. Residues of red pigment are still visible on the face, leading researchers to conclude that, at some point, the Sphinx's entire visage was painted red. Traces of blue and yellow paint elsewhere suggest to Lehner that the Sphinx was once decked out in gaudy comic book colours.
One of the many mysteries of the Sphinx revolves around its true name. 'Sphinx' is the name of the human-headed winged lion in ancient Greek mythology, but the term likely only came into use some 2,000 years after the statue was built.
There are hundreds of tombs at Giza with hieroglyphic inscriptions dating back some 4,500 years, but not one mentions the statue. "The Egyptians didn't write history," says Egyptologist James Allen, from Brown University, in Rhode Island, "so we have no solid evidence for what its builders thought the Sphinx was ... Certainly something divine, presumably the image of a king, but beyond that is anyone's guess."
Likewise, the statue's symbolism is unclear, though inscriptions from the era refer to Ruti, a double lion god who sat at the entrance to the underworld and guarded the horizon where the Sun rose and set. This corresponds to Lehner's current belief that the Sphinx was built to help the Egyptians harness the power of the Sun.
The question of who built the Sphinx has long vexed Egyptologists and archaeologists. Lehner, Hawass and others agree it was Pharaoh Khafre, who ruled Egypt during the Old Kingdom, which began around 2600 BC and lasted some 500 years before giving way to civil war and famine.
It's known from hieroglyphic texts that Khafre's father, Khufu, built the 147 m tall Great Pyramid, not far from where the Sphinx would later be built. Khafre, following a tough act, constructed his own pyramid, only three metres shorter than his father's, close to the Sphinx. Some of the evidence linking Khafre with the Sphinx comes from Lehner's research, but the idea dates back to 1853.
That's when a French archaeologist named Auguste Mariette unearthed a life-size statue of Khafre, carved with startling realism from black volcanic rock, amid the ruins of what would later be called the Valley Temple of Khafre. What's more, Mariette found the remnants of a stone causeway connecting the Valley Temple to a mortuary temple next to Khafre's pyramid. Then, in 1925, French archaeologist and engineer Emile Baraize probed the sand directly in front of the Sphinx and discovered yet another Old Kingdom building - now called the Sphinx Temple - strikingly similar in its ground plan to the ruins Mariette had found.
Despite these clues tying the Sphinx to Khafre's pyramid and temples, some experts continued to speculate that Khufu or other pharaohs built the statue. Then, in 1980, Lehner recruited a young German geologist, Tom Aigner, who suggested a novel way of showing that the Sphinx was part of Khafre's larger building complex.
Limestone is the result of mud, coral and the shells of plankton-like creatures compressed together over tens of millions of years. Looking at samples from the Sphinx Temple and the Sphinx itself, Aigner and Lehner inventoried the different fossils making up the limestone. The fossil fingerprints showed that the blocks used for the wall of the temple must have come from the ditch surrounding the Sphinx - as the statue was being carved, the quarried blocks were being hauled away to build the temple.
But who carried out the backbreaking work of creating the Sphinx? The first insight came in 1990 when an American tourist was thrown from her horse around 800 m south of the Sphinx after it stumbled on a low mud-brick wall.
Hawass investigated and discovered an Old Kingdom cemetery. Some 600 people were buried there, with tombs belonging to overseers - identified by inscriptions recording their names and titles - surrounded by the more humble tombs of labourers.
But little was known about these workers until 1999, when Lehner found what had originally drawn him to Egypt - a Lost City. It wasn't the archives of Atlantis that he had long given up on, but a settlement near the cemetery dating back to Khafre's reign.
When Lehner and Hawass excavated and mapped the area they found four clusters of eight long mud-brick barracks. Each had the elements of an ordinary house - a pillared porch, sleeping platforms and a kitchen - enlarged to accommodate around 50 people sleeping side by side. The barracks, Lehner says, could have accommodated between 1,600 to 2,000 workers - or more, if the sleeping quarters were on two levels.
The workers' diet indicates they weren't slaves. Lehner's team found remains of mostly male cattle under two years old - in other words, prime beef. Lehner thinks ordinary Egyptians may have rotated in and out of the work crew under some sort of national service or feudal obligation to their superiors.
Forty-five centuries ago, the workers would have lacked iron or bronze tools; they mainly used stone hammers, along with copper chisels for detailed finished work. Rick Brown, a professor of sculpture at the Massachusetts College of Art and Design, attempted to learn more about the construction of the Sphinx by sculpting a scaled-down version of its missing nose from limestone, using replicas of ancient tools found on the Giza plateau and depicted in paintings.
Brown, assisted by art students, found that the copper chisels became blunt after only a few blows and needed re-sharpening in a furnace that Brown had constructed. Lehner and Brown estimate one labourer might carve 30 cm3 of stone a week. At that rate, they say, it would have taken 100 people three years to complete the Sphinx.
But it seems Khafre's vision was never fully realised. There are signs the Sphinx was unfinished.
In 1978, in a corner of the statue's quarry, Hawass and Lehner found three stone blocks, abandoned as labourers were dragging them to build the Sphinx Temple. The north edge of the ditch surrounding the Sphinx contains segments of bedrock that are only partially quarried. Here the archaeologists also found the remnants of a workman's lunch and tool kit - fragments of a beer or water jar and stone hammers.
Apparently, the workers walked off the job.
By the time the Old Kingdom finally broke apart around 2130 BC, the desert sands had begun to reclaim the Sphinx. For the next seven centuries the colossus was buried up to its shoulders, creating a disembodied head atop the eastern edge of the Sahara. It would sit ignored for the next seven centuries, until it appeared to a young prince in a dream.
According to the legend engraved on a pink granite slab nestled between the Sphinx's paws, the Egyptian prince Thutmose went hunting in the desert, grew tired and lay down in the shade of the Sphinx.
In a dream, the statue, calling itself Horemakhet - or Horus-in-the-Horizon, the earliest known Egyptian name for the statue - addressed him. It complained about its ruined body and the encroaching sand. Horemakhet then offered Thutmose the throne in exchange for help.
When he became Pharaoh Thutmose IV, he helped introduce a Sphinx-worshipping cult to the New Kingdom (1550–1070 BC). Across Egypt, sphinxes appeared everywhere in sculptures, reliefs and paintings, often depicted as a symbol of royalty and the sacred power of the Sun.
Based on an analysis of the many layers of stone slabs placed like tilework over the Sphinx's crumbling surface, Lehner believes the earliest attempt to restore the statue may date back as far as 3,400 years, to Thutmose's time, in keeping with the legend of Horemakhet.
But despite Thutmose's efforts and many subsequent attempts, it wasn't until the late 1930s that the statue was finally freed from the sand by Egyptian archaeologist, Selim Hassan. "The Sphinx has thus emerged into the landscape out of shadows of what seemed to be an impenetrable oblivion," the New York Times declared.
The rolling sand dunes and vicious sandstorms that once buried the Sphinx now characterise Northern Africa; but the Sahara has not always been a barren desert. German climatologists Rudolph Kuper and Stefan Kröpelin, analysing the radiocarbon dates of archaeological sites, recently concluded that the region's prevailing climate pattern changed around 8500 BC, with the monsoon rains that covered the tropics moving north.
The desert sands sprouted rolling grasslands punctuated by verdant valleys, prompting people to begin settling the region in 7000 BC (see "Valley of the whales", Cosmos 10). Kuper and Kröpelin say this green Sahara came to an end between 3500 BC and 1500 BC, when the monsoon belt returned to the tropics and the desert re-emerged. That date range is 500 years later than prevailing theories had suggested.
Further studies led by Kröpelin revealed that the return to a desert climate was a gradual process spanning centuries. This transitional period was characterised by cycles of ever-decreasing rains and extended dry spells.
Support for this theory can be found in recent research conducted by Judith Bunbury, a geologist at the University of Cambridge. After studying sediment samples in the Nile Valley, she concluded that climate change in the Giza region began early in the Old Kingdom, with desert sands arriving in force late in the era.
The implication is that the Sphinx and the pyramids, epic feats of engineering and architecture, were built at the end of a special time of more dependable rainfall, when pharaohs could marshal labour forces on an epic scale. But then, over the centuries, the landscape dried out and harvests grew more precarious.
The pharaoh's central authority gradually weakened, allowing provincial officials to assert themselves and eventually culminating in an era of civil war.
The research also helps explain some of Lehner's findings about the current state of the Sphinx. His investigations at the Lost City revealed that the site had suffered dramatic erosion; some structures had been reduced to ankle level over three to four centuries after their construction. "So I had this realisation," he says, "this buzz saw that cut our site down is probably what also eroded the Sphinx."
It's possible that the patterns of erosion on the Sphinx are due to changing climate conditions with intermittent wet periods dissolving salt deposits in the limestone, which then recrystallised on the surface. This caused softer stone to crumble while harder layers formed large flakes that would be blown away by desert winds during the dry times.
The Sphinx, Lehner says, was subjected to constant 'scouring' during this transitional era of climate change.
"It's a theory in progress," says Lehner. "If I'm right, this episode could represent a kind of 'tipping point' between different climate states - from the wetter conditions of Khufu and Khafre's era to a much drier environment in the last centuries of the Old Kingdom."
Today, the Sphinx is still eroding. Three years ago, Egyptian authorities learned that sewage dumped in a nearby canal was causing a rise in the local water table. Moisture was being drawn up into the body of the Sphinx and large flakes of limestone were peeling off the statue.
Hawass arranged for workers to drill test holes in the bedrock around the Sphinx. They found the water table was only about five metres beneath the statue. Pumps have since been installed nearby to divert the groundwater.
So far, so good - but the fight won't end here. "Never say to anyone that we saved the Sphinx," says Hawass. "The Sphinx is the oldest patient in the world. All of us have to dedicate our lives to nursing the Sphinx all the time."
Author: Evan Hadingham | Source: Issue 32 of Cosmos [April 2010]