Buried within the ruins of an ancient village in central Turkey, alongside tools and trash, are the bodily wastes of the people—and goats—who lived there 10,000 years ago. Whereas the dung was used for fuel and building material, salts from the urine remain trapped in layers of sediment beneath the village. Now, archaeologists have used these salts to re-create parts of the village’s 1000-year history, including its 500-year process of partial animal domestication.
Archaeologists don’t normally look for urine salts, but because of central Turkey’s arid environment—and the plastered floors of old buildings that protected the dirt underneath—researchers thought some of them might linger behind in the dirt at the site, called Aşıklı Höyük.
They weren’t disappointed. They found large concentrations of salts in each sediment layer at Aşıklı Höyük, which revealed how many mammals, human and nonhuman alike, made the village their home from approximately 8450 B.C.E. to 7450 B.C.E. The researchers estimated how much human waste must have been produced based on the number of excavated homes in each layer. The remaining urine salts, the scientists say, reflect how many sheep or goats lived in or near the village at a time.
In the village’s first hundred years, when humans in Anatolia were just beginning to abandon a nomadic hunter-gatherer lifestyle, very few additional salts appear—only enough for a few animals at a time. But over the next 400 years, the sheep and goats living at Aşıklı Höyük multiply by a factor of 10 roughly every few centuries, the team reports today in Science Advances.
In the most recent layer, beginning around 7900 B.C.E., the villagers appear to have moved their flock to the settlement’s fringe, where there were more sheep and goats than the estimated 500 to 1000 people who lived in the village. That move suggests the villagers had slowly transitioned from capturing a few wild animals to herding and breeding a large group of semidomesticated ones. But the slow pace of that move suggests to researchers that this process of domestication likely got started by accident.