Nearly 10,000 years ago, the rise of farming paved the way for large settlements in a swathe of the Middle East — and might have protected one such settlement from certain parasites.

Piers Mitchell at the University of Cambridge, UK, and his colleagues analysed fossilized faeces that they unearthed in modern-day Turkey at a site called Çatalhöyük, which is often referred to as an early town. First occupied in 7100 BC, the site now provides a key record of the transition to settled life.

The team found eggs from whipworm (Trichuris trichiura), a parasite that causes malnutrition, in two human poos from the site. Whipworm is spread by food and water contaminated with infested faeces.

Other sites from Çatalhöyük’s time period hosted a broad range of parasite species, including some that are transmitted from animals to humans. But at Çatalhöyük itself, researchers found only whipworm. This parasite was also common at sites occupied later than Çatalhöyük, such as Bronze- and Iron-age settlements.

Çatalhöyük’s infrastructure and cultural practices, such as farming, might have reduced the risk that residents would contract parasites from animals, while promoting the risk of parasites that spread from human to human, the authors say.