Myth busted: our ancestors ate carbs and veg, not just meat

The Cradle of Humankind has been the poster child of archaeology in the past few years, with a strong emphasis on our origins as a species.

From the discovery of australopithecus sediba, to the more recent and much-celebrated homo naledi, this fossil-rich landscape has become an obsession for archaeologists and tourists alike as we try to figure out our family tree.

However, a recent groundbreaking discovery at the Border Cave in the Lebombo Mountains on the KZN/eSwatini border is a strong reminder that our country also has archaeological jewels that shed light not on our origins as a species but more on how we lived as a species in the very distant past – and when exactly certain cultural practices appeared.

The latest find came in the form of charred pieces of starchy vegetables found in the ashes of the cave from 170,000 years ago, and reveals that early modern humans feasted on starchy food that they cooked over a fire.

This changes the notion of a meat-only paleo diet in the Middle Stone Age, and also shows that we need to rethink our timeline of when we began the practice of roasting vegetables.

“I think people were eating a very balanced diet, a combination of carbohydrates and proteins,” lead researcher Lyn Wadley from the Wits Evolutionary Studies Institute told New Scientist.

The team found the ashes in 2016 and then got to work – for three years – with a  microscope exploring every fragment in detail. That was how they came across the charred fragments of the starchy plants.

“This discovery is much older than earlier reports for cooking similar plants and it provides a fascinating insight into the behavioural practices of early modern humans in Southern Africa. It also implies that they shared food and used wooden sticks to extract plants from the ground,” said Wadley.

The plants, Hypoxis rhizomes (underground stems), are extremely fragile and, according to Dr Christine Sievers, also from Wits University, “it is extraordinary that they survived for so long”.

This isn’t the first time the Border Cave has busted archaeological myths of when indigenous South Africans (San hunter-gatherer communities) began certain practices.

In 2012, an international team (including researchers from Wits) greatly increased the age at which the emergence of modern culture began.

“A key question in human evolution is when in prehistory human cultures similar to ours emerged,” Wits University said at the time. Until the 2012 research, “most archaeologists believed that the oldest traces of San hunter-gatherer culture in Southern Africa dates back 10,000, or at most 20,000 years.”

The results showed without a doubt that it was actually around 44,000 years ago that the people at Border Cave were using digging sticks weighted with perforated stones, like those traditionally used by the San.

Details also emerged of ostrich egg and marine shells being used for adorning the body, and notched bones for counting, as well as decorated and poisoned arrowheads for hunting.

The latest find is now adding substantial pieces to the puzzle of how the San lived at the time.

“The Border Cave inhabitants would have dug Hypoxis rhizomes from the hillside near the cave, and carried them back to the cave to cook them in the ashes of fireplaces,” says Wadley.

“The fact that they were brought back to the cave rather than cooked in the field suggests that food was shared at the home base. This suggests that the rhizomes were roasted in ashes and that, in the process, some were lost.”

With an international team’s eyes on the cave, which has been under scrutiny for almost a century, more details are likely to emerge as advanced technology improves the way remnants can be explored.