Tooth enamel helps solve the mystery of an ancient Greek cemetery

An ASU PhD candidate is working to piece together the lives of people who were found buried in shackles in a Greek cemetery by studying teeth.

The Faleron Cemetery was first discovered in the early 1900s and contains the remains of children, shackled men and even animals. Using ceramics, the site has been dated to the Archaic period in Athens, between the 8th and 7th centuries BC.

A major excavation was conducted from 2012-16 by Greek archaeologist Stella Chrysoulaki, but despite the excavation, answers to many questions - including the identity of those found in shackles - were never found.

To help answer these questions, experts turned to Arizona State University, and the Faleron Bioarchaeology Project was created.

The project is led by ASU Regents Professor Jane Buykstra and currently includes the work of ASU Professors Kelly Knudson and Chris Stojanowski and PhD candidate Julianne Stamer.

"We have many supporters and collaborators from the U.S. and Europe, including scientists and humanists, which makes this work challenging but rewarding," says Buikstra. "There are graduate students and early career professionals involved, which is always energizing."

Now as part of the project, Stamer is writing part of his dissertation on a mass grave that contains three rows of people buried at the Faleron Cemetery site.

Esplanade

Anthropologists and archaeologists have named these three graves "Esplanade".

Stamer will also compare people on the Esplanade with others buried in different parts of the cemetery.

The Esplanade contains the remains of 79 shackled people believed to be victims of political violence. Some of them are shackled above their heads, others at their feet. Scientists have determined the age and gender of the remains and they are believed to be young men, Stamer said.

"We are getting preliminary data on the residential history of people at this site - that means we have used strontium stable isotope analysis to determine whether the people buried at Faleron were born near Athens or not," she said.

With the help of ASU's Metals, Environment and Land Analytical Laboratory, or METAL, Stamer analyzes strontium in tiny samples of the men's tooth enamel.

Stamer says she does this with extra care and respect for the buried people and that she is cooperating with the Greek government.

Before Stamer takes the enamel, she makes 3D models of the teeth, documents all of her work and must honor all permits. She also said the samples she uses will be returned to Greece when she is finished; ASU does not store tooth enamel.

Science

Julianne Stamer will visit the Roman Agora in Athens in the summer of 2023.

With metal, Stamer takes about 30 milligrams of tooth enamel, which is equivalent to about 100 grains of sand or less.

Teeth can reveal your entire life story, says Stamer.

Tooth enamel is different from bone. Enamel is formed in early childhood, and it doesn't regenerate when you chip or break a tooth. Bones, however, do repair themselves, and the cells and mineral composition change over the course of a lifetime, which is why our bones don't usually show until the last seven years of life.

"From the time your teeth are formed in infancy, they have the same mineral composition," says Stamer. "One of the minerals found in teeth is strontium, a metal that has several stable isotopes that have different weights depending on the atomic number.

"Strontium is found in nature, and we also find it in soil and water. Strontium isotopes vary depending on the type of soil or rock from which they were derived. So what we're really saying is that the ratio of the heavier strontium isotope to the lighter strontium isotope matches what we assume the local geology of Athens should look like."

METAL at ASU incorporates state-of-the-art technology for bioarchaeologists to conduct research.

Gwyneth Gordon, lab manager and assistant research professor in the School of Earth and Space Studies, said the lab has been developing specialized techniques and devices specifically for anthropology for more than 20 years.

"We have a fume hood in the trace metal purity lab for our anthropology researchers, certified standards developed for common sample types such as bone and dental enamel, and specially designed analytical workflows to achieve the highest possible data quality for anthropologists," Gordon says. "We also have two Prepfast-MC instruments that automate sample preparation for the determination of strontium isotopes in dental enamel. We worked with the company to validate its use for this very purpose."

Stamer has been working on the project since 2020 and hopes to complete the lab analysis this academic year. She also revealed that other researchers on the project are working on ancient DNA (aDNA) - but to date, no aDNA has been found for individuals from the Esplanade.

For Stamer, this work is more than a dissertation.

"I think we can learn a lot about the people buried on the Esplanade," she said.

"I think we can learn to empathize with people in different times and places. We can learn how similar we are to others and at the same time how different we are. People like to hear about history and classical studies. Bioarchaeology adds a humanistic side to classic literature."