ABOVE: The remains of a Stone Age young adult with an apparently amputated left leg Fig 3A from Maloney et al., Nature, doi:10.1038/s41586-022-05160-8, 2022. CC BY 4.0

The remains of a young adult who lived 31,000 years ago in what is now Borneo exhibit telltale signs of surgical amputation, a study published today (September 7) in Nature reports. The case predates the previous earliest evidence for a complex medical procedure by roughly 24,000 years and suggests the advent of surgery occurred thousands of years before that of ceramics.

Tim Maloney, an archaeologist at Griffith University in Australia and coauthor of the paper, said in a press briefing that the case “rewrites the history of human medical knowledge and developments,” the Associated Press reports. It indicates that hunter-gatherers were capable of “quite advanced forms of healthcare,” coauthor Melandri Vlok of the University of Sydney tells New Scientist.

The research team found the remains while working in a region of Borneo known for its Stone Age rock art. The skeleton was largely intact but lacked a left foot and the lower parts of its left fibula and tibia—the two bones of the lower leg. Both bones ended in a slanted cut that healed cleanly with no signs of infection or the kind of fractures that occur when a bone is crushed, leading the researchers to conclude that the limb had been amputated. Further examination of the remains indicated that the procedure likely occurred six to nine years prior to the person’s death at age 19 or 20.

Alecia Schrenk, an anthropologist at the University of Nevada, Las Vegas, who was not involved in the study, tells the AP that such procedures weren’t previously thought to occur in pre-agricultural societies. “It had long been assumed healthcare is a newer invention,” Schrenk wrote in an email to the outlet. “Research like this article demonstrates that prehistoric peoples were not just left to fend for themselves.”