Little Foot unveiled (Photo Credit: University of Witwatersrand)

On December 6, Little Foot, the most complete skeleton of a human ancestor ever found, made its debut at the Hominin Vault at University of Witwatersrand's Evolutionary Studies Institute in Johannesburg, South Africa. The ancient fossil’s public unveiling ends a painstaking journey of discovery and assembling that began in 1994, when paleoanthropologist Ron Clarke stumbled upon fragments of four left foot bones while rummaging through a museum box.

Convinced they were from the same hominin, or early human ancestor, the scientist decided to investigate further. Three years later, in 1997, he found new foot bones belonging to the same individual from the fossil trove of the university’s medical school. Believing there may be more, the researcher and his team headed to South Africa’s Sterkfontein cave system, where the bones had been unearthed.

Little Foot skull (Photo Credit: University of Witwatersrand

It was a slow, arduous, task that required the use of small, needle-like tools. Clarke, who likens the endeavor to “excavating a fluffy pastry out of concrete,” says, "The process required extremely careful excavation in the dark environment of the cave. Once the upward-facing surfaces of the skeleton's bones were exposed, the breccia in which the undersides were still embedded had to be carefully undercut and removed in blocks for further cleaning in the lab.”

But it was well worth it. Little Foot, who was a female, is not just the first complete ancient adult skeleton found, but also the first with a complete leg and arm in one individual. In contrast, Little Foot’s more famous counterpart, Lucy, discovered in East Africa in 1974, is only 40 percent complete and lacks a head.

General view of Little Foot skeleton in its original position in Sterkfontein cave November 2006 (Photo Credit: V. Mourre via Wikipedia commons)

The mammal, which belongs to the genus Australopithecus, had short arms and small hands, indicating she was more similar humans than apes. Assumed to be in her 30’s, Little Foot is believed to have died after falling into a sinkhole from a tree where she was sleeping. The researchers still need to investigate where she fits into the human family tree and her food preferences.

Estimated to have lived on Earth 3.67 million years ago, Little Foot is the oldest human ancestor ever found in Southern Africa. She is not however the oldest. That honor goes to Ardi, a hominin that lived in Ethiopia 4.4 million years ago. But given that Little Foot is over 90 percent complete, she is far more valuable to researchers. The significance is not lost on Clarke, who proudly asserts, “Little Foot is one of the most remarkable fossil discoveries made in the history of human origins research.”

Resources: Smithsonian.org, nationalgeographi.com, wikipedia.org