The remains of prehistoric pots unearthed in North African have just yielded the first known direct evidence for early humans’ cooked vegetables, grains and other plant products.

Researchers determined that the food found stuck on the nearly 10,200-year-old pots was a “kind of porridge,” which might be used as a staple diet whenever there was lack of meat from hunting.

The fragments of the pottery were unearthed at two different sites in the Libyan Sahara, which was green and fertile at the time. Early humans’ ability to cook plants and grains in pots is considered as a big advancement on the way to civilization.

Dr. Julie Dunne, a researcher from the University of Bristol, said, “This is the first direct evidence of plant processing globally, and, remarkably, shows that these early North African hunter-gatherers consumed many different types of plants, including grains/seeds, leafy plants and aquatic plants.”

The researchers also determined that the prehistoric cooked food remains are so old that they predate start of plant domestication and agriculture in the region by more than 4,000 years

The first direct evidence of prehistoric plant cooking was reported in the most recent issue of the journal Nature Plants.