The Great Sphinx of Giza is one of the most recognizable sculptures from ancient Egypt, and the mysteries of its construction some 4,500 years ago have long fascinated archaeologists. Now, new research suggests that nature may have played a key role in crafting the Sphinx’s shape.
Yardangs are made from wind erosion. As the desert blows sand onto rock formations, softer pieces erode while harder sediments remain. Some yardangs are tall like towers, while others are more squat—and some may even end up looking strangely sphinx-like.
“Our results provide a simple origin theory for how sphinx-like formations can come about from erosion,” says study senior author Leif Ristroph, an experimental physicist and applied mathematician at New York University (NYU), in a statement. “There are, in fact, yardangs in existence today that look like seated or lying animals, lending support to our conclusions.”
Given the Sphinx’s shape, researchers have previously wondered whether the sculpture was made from a yardang. The NYU team’s work provides important new evidence to support this theory’s plausibility.
To recreate how the Sphinx could have formed from a yardang, Ristroph and his team took a shapeless mound of clay and embedded harder materials inside it to replicate the terrain in northeastern Egypt. They then ran a fast-flowing stream of water over it, a process that mimicked wind erosion. The researchers monitored how the clay changed using a 3D optical scanner. Eventually, a sphinx-like shape appeared.
“The harder or more resistant material became the ‘head’ of the lion, and many other features—such as an undercut ‘neck,’ ‘paws’ laid out in front on the ground and arched ‘back’—developed,” say the researchers in the statement.
If similar shapes formed over many years in the desert, such natural rock formations “could have put in the minds of these ancient Egyptians that there are these great, mythical animals that are sitting out there,” says Ristroph to Eos’ Nathaniel Scharping.
While the NYU team demonstrated that a yardang could have plausibly shaped the Sphinx, their work doesn’t definitively settle the question of how it was constructed.
“It’s not so black and white,” Ristroph tells CNN’s Taylor Nicioli. “No one says this is an entirely human-carved thing, and no one says it’s entirely nature-carved. The question is how much was naturally existing and then further modified.”
Kathryn Bard, an archaeologist at Boston University who wasn’t involved in the study, is cautiously optimistic.
The study shows “a very real possibility of how a natural limestone formation came to have a kind of amorphous sphinx-like shape,” Bard tells Live Science’s Owen Jarus. At the same time, she says she’s familiar with yardangs at the Dakhla Oasis in Egypt’s Western Desert, and the one produced by the new study doesn’t resemble any she has seen before.
Regardless of wind erosion’s role, researchers agree that the Great Sphinx would have required hard-working and highly skilled craftsmen. As Ristroph tells Live Science, there is “no doubt that the facial features and detail work was done by humans.”
Editor’s note, November 14, 2023: This story has been updated to reflect the fact that the Great Sphinx was constructed 4,500 years ago, not 2,500 years ago.