When the site of Wadi Sura II was discovered in Egypt's Western Desert in 2002, researchers were taken aback at the thousands of decorations painted on the walls of the rock shelter as much as 8,000 years earlier. Not only are there wild animals, human figures, and odd headless creatures that have led people to nickname it the "Cave of the Beasts," but also hundreds of outlines of human handprints — more than had ever been seen before at a Saharan rock art site.

Even more unusual are outlines of 13 tiny handprints. Until the discovery of Wadi Sura II, the stenciled hands and feet of very small children had been seen in Australian rock art, but never in the Sahara. One notable, touching scene even features a pair of "baby" hands nestled inside the outlines of a larger, adult pair.

Now it gets even odder: The tiny hands aren't even human.

Seeking Answers in a French Hospital

Wadi Sura II is considered one of the greatest rock art sites of the Sahara, although it lacks the popular fame of nearby Wadi Sura I, the "Cave of the Swimmers," which was discovered by Hungarian count Láslo Almásy in 1933 and popularized in "The English Patient."

Anthropologist Emmanuelle Honoré of the McDonald Institute for Archaeological Research describes how she was "shocked" by the shape of the unusually small hand outlines when she saw them at her first visit to Wadi Sura II in 2006. "They were much smaller than human baby hands, and the fingers were too long," she explains.

Honoré decided to compare measurements taken from the hand outlines with those taken from the hands of newborn human infants (37 to 41 weeks gestational age). Since the site samples were so physically small, she also included measurements taken from newborn premature babies (26 to 36 weeks gestational age).

For that, the anthropologist recruited a team that also included medical researchers to collect the infant data from the neonatal unit of a French hospital. "If I went to a hospital and just said, 'I'm studying rock art. Are there babies available?' they'd think I'm crazy and call security on me," she laughs.

The results, which have just been published, show that there's an extremely low probability that the "baby" hands in the Cave of the Beasts are actually human.

The Challenge of Interpretation

So if the prints aren't human, what are they? The positioning of the tiny hands and their fingers varies from outline to outline, which led the research team to conclude they were flexible and articulated and ruled out the possibility of a stencil fashioned from a static material like wood or clay.

View Images The walls of Wadi Sura II are covered with hundreds of hand stencils, as well as images of people, wild animals and unusual headless beasts. Photograph by Emmanuelle Honoré

Honoré initially suspected monkey paws, but when those proportions were also off, colleagues at the Museum of Natural History in Paris suggested she take a look at reptiles.

So far, the examples that have proportions closest to the "baby" hands come from the forelegs of desert monitor lizards or, possibly, the feet of young crocodiles. (The crocodile study is still in progress.) Monitor lizards still live in the region today and are considered protective creatures by nomadic tribes in the area.

The revelation that the small hand images from Wadi Sura II are not even human is a big surprise for researchers who study Saharan rock art. "Animal stenciling is mostly considered an Australian or South American thing," Honoré explains.

The animal feet decorations in Wadi Sura II appear not only stenciled inside the outlines of human hands but also in friezes, a patterning also seen with human hands. All were stenciled around the same time with the same pigment. It's impossible to say, however, whether the foot of a live creature was pressed against the wall of the rock shelter for stenciling or whether the artist(s) opted for the convenience and safety of a freshly severed limb.

Honoré is reluctant to speculate too much on the meaning of the non-human prints. "We have a modern conception that nature is something that humans are separate from," she says. "But in this huge collection of images we can detect that humans are just part of a bigger natural world. It's very challenging for us as researchers to interpret these paintings since we have a culture that's totally different [from the one that created it]. "

Meanwhile, many of the parents whose babies participated in the research are looking forward to reading about the rock art revelation. "They were really enthusiastic about the idea that their newborns could make such a contribution to science," says Honoré.

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