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The turkey on your Thanksgiving table is older than you think

If you celebrate Thanksgiving, you’re taking part in a culinary tradition that traces back thousands—not hundreds—of years. Turkeys served as ceremonial centerpieces for Mayan rulers as early as 350 B.C.E., according to archaeologist Erin Thornton at Washington State University in Pullman.

Thornton and her mentor, Kitty Emery, curator of environmental archaeology at the Florida Museum of Natural History in Gainesville, have been shining a light on the early domestication of turkeys for more than a decade. Their work was the first to reveal that Mayans raised and managed wild turkeys (Meleagris gallopavo)—the same species as the Butterball on your table—more than 2300 years ago, making them the first vertebrates to be domesticated on the North American continent.

Thornton spoke with Science about how archaeologists look for evidence of early domestication in these birds and what they meant for the ancient civilizations that reared them. The conversation has been edited for clarity and length.

Q: What got you interested in turkeys?

A: In grad school I was working at a site called El Mirador in northern Guatemala. It’s famous for being one of the earliest, biggest Maya cities. I was studying animal bones found at a site called the Jaguar Paw Temple. I found turkeys, and some of them looked like Meleagris gallopavo, the wild turkey, which is found throughout the eastern U.S., the American Southwest, and down into much of Mexico. The bones did not belong to the ocellated turkey [M. ocellata], which is native to the Mayan region. My adviser assumed I must have made a mistake. But eventually through genetic evidence we proved they were indeed wild turkeys.

Q: How did these wild turkeys get to Guatemala?

A: It is difficult to say. They were very likely reared on-site rather than being imported. An animal’s diet is reflected in biochemical markers called isotope ratios. As an animal feeds and drinks, strontium, a type of metal found in soil, is incorporated into their body tissues, including bones. Strontium values in the El Mirador turkeys match the local strontium values at the site, which are very different from the values found in central Mexico.

The turkeys could have initially been obtained via trade or gifting, as there is evidence of the movement of other materials from Central Mexico into the Maya. It is also possible that people from central Mexico brought them there directly, but this is a more difficult idea to prove.

Q: How do we know the Mayans domesticated the birds?

A: One of the best ways to look at early domestication is through reconstruction of ancient diets. So again, we turn to isotope ratios. We can test stable isotope ratios in archaeological bones to see when they switched from a wild diet to being fed something like corn. That really is the way we’re identifying the earliest domestic turkeys. They start eating the same things that the humans are eating.

And that’s what we see in the bones from El Mirador. Isotope analysis reveals they were eating a substantial amount of corn in their diets.

Q: What’s so special about turkeys?

A: Turkeys are large-bodied. They’re pretty tame. They’ll feed in agricultural fields; they like the insects that are found in cornfields. People may have tolerated their presence in the fields because they’re excellent insect removers. They’re essentially pest control. And turkeys have a tolerance for human-disturbed environments. We see that even around our communities today. If we’re not hunting them like crazy, they persist in the fields and settlements.

Q: Did the ancient Mayans eat a lot of turkey?

A: It doesn’t seem so. The theme that really emerges in terms of animal domestication in Mesoamerica is that it’s not necessarily about food. People were eating dogs and turkeys, but primarily for elite display—things like feasting or rituals. They’re not necessarily being used to feed the masses.

Q: That sounds a bit like Thanksgiving feasts today.

A: It totally is. The turkey is the only vertebrate animal domesticated on the North American continent. Dogs were already domesticated when they accompanied humans into the Americas. Horses, cows, pigs, chickens—all of those were introduced from other places.

So in my mind, it really is this iconic American bird with a long history of importance, and now it’s celebrated at Thanksgiving. It’s changed quite a bit in its meaning, but there’s this continuity of symbolic importance.

Q: White meat or dark meat?

A: Both. Probably a little more dark meat. But unfortunately we’re traveling over Thanksgiving so I won’t be having either this year. I’ll probably make up for it later.