Ancient faeces reveals early settler parasite infection
Whipworm eggs found in 8000-year-old human coprolites. Andrew Masterson reports.
Researchers picking though 8000-year-old human faeces have identified the earliest evidence of intestinal parasite infection in the mainland Near East.
A team led by archaeologist Piers Mitchell of Cambridge University in the UK travelled to the well preserve remains of a prehistoric village called Çatalhöyük, in southern Anatolia.
The site was occupied from about 7500 to 5700 BCE, and is today a UNESCO World Heritage Site.
Apart from the extraordinarily good state of its survival, the village is of key interest because it was occupied around the period that populations in the region shifted from foraging to farming.
The change in both diet and lifestyle – particularly the emergence of permanent settlements – introduces the question of whether such a shift in living conditions also brought about a consequent change in disease profiles.
One key challenge all early settlers faced was the need to manage human waste. In the matter of Çatalhöyük, faeces was disposed of in the village midden, or dumped. It is thought that villagers either went to the toilet directly in the midden, or did their business in their homes in clay bowls and then carried the results.
Either way, Mitchell and his colleagues were able to excavate four fossilised human turds, known as coprolites, from the site. They also took samples of soil beneath the pelvic areas of skeletons resting in graves.
All the samples taken dated from between 7100 and 6150 BCE. Analysis of the sterols and bile acids found within them, using a mass spectrometer, confirmed the faeces as human.
Microscopic analysis revealed that two of the coprolites contained the eggs of whipworms (Trichuris trichiura), a parasitic roundworm three centimetres long that infects the human large intestine and can live for up to five years. Heavy infestations can have severe health outcomes, especially in children.
The discovery of the parasite eggs established a new benchmark for their presence in humans in the region.
“It was a special moment to identify parasite eggs over 8000 years old,” says study co-author Evilena Anastasiou.
Another co-author, Marissa Ledger, explains that the depositing of faeces within the village midden was a prime opportunity for the worms.
“We would expect this to have put the population at risk of diseases spread by contact with human faeces, and explains why they were vulnerable to contracting whipworm,” she says.
“As writing was only invented 3000 years after the time of Çatalhöyük, the people were unable to record what happened to them during their lives. This research enables us for the first time to imagine the symptoms felt by some of the prehistoric people living at Çatalhöyük who were infected by this parasite.”
One important question remains unanswered, however. Although the parasitic infection is assumed to be the result of permanent settlement, one all-important piece evidence remains missing.
“Now we need to find ancient faecal material from prehistoric hunter gathers in the Near East, to help us understand how this change in lifestyle affected their diseases,” says Mitchell.
The research is published in the journal Antiquity.