A tiny mark in a Neolithic mudbrick is pointing researchers to a big shift in the history of bread wheat.

A new study suggests bread wheat likely emerged about 8,000 years ago in the South Caucasus region through a natural hybridisation process involving already domesticated wheat and a wild grass species. The findings were published in the Proceedings of the National Academy of Sciences, or PNAS.

The study is based on archaeological work by the Georgian National Museum at the ancient settlements of Gadachrili Gora and Shulaveris Gora, which date to the Neolithic period. Excavations at the sites found botanical evidence including wheat spike impressions preserved in ancient mudbrick and plant remains that point to early agricultural experimentation.

Gadachrili Gora and Shulaveris Gora are part of the Shulaveri-Shomutepe cultural tradition, which developed in the South Caucasus, spanning southeastern Georgia, western Azerbaijan and northern Armenia, about 8,000 to 7,300 years ago.

David Lordkipanidze, director of Georgia’s National Museum, said the find adds to evidence that Georgians were among the first farmers.

“Here we have 8,000 years of traces of bread wheat, as well as we found here some years ago 8,000 years of traces of wine making. So, we can say for sure that here in Georgia, we discovered traces of bread wheat and winemaking, which dates back 8,000 years,” he says.

Archaeological and genetic studies have shown the region was home to early farming communities that cultivated a wide variety of crops.

Nana Rusishvili, a paleoethnobotanist at Georgia’s National Museum, has studied archaeobotanical material from Gadachrili Gora for decades. She said the samples show evidence that early domesticated wheat crossed with a wild grass species known as Aegilops tauschii.

“This gives us the possibility to prove that on the Georgian territory, the bread wheat has been originated and as a result, Georgia is one of the centers of bread wheat domestication,” she says.

The region is also regarded as the birthplace of wine.

Melinda Zeder, an archaeologist at the Smithsonian’s National Museum of Natural History, said the study helps show how the domestication process unfolded. She said it indicates early farmers in the South Caucasus were in contact with neighbouring regions, gaining knowledge and adapting it to local climate and environmental conditions.

“So this really makes the invention of this bread wheat a product of that kind of inventiveness, innovation, on the part of the indigenous people in the South Caucasus that were drawing on those technologies,” Zeder says.

The Caucasus and Georgia form part of what is known as the Fertile Crescent, a swathe of fertile land stretching from Upper Egypt to Mesopotamia, now modern-day Iraq, Kuwait and northeast Syria. It is often referred to as the “Cradle of Civilization” and is believed to be the birthplace of early agriculture and modern human civilizations.

Read more from the study here.