The Origins of Turkeys Were Never What We Thought — Ancient DNA Finally Revealed The Truth

[00:00:00]400 years ago, a Spanish soldier stopped in front of a cage of large dark birds with iridescent feathers and naked red heads and realized the Aztecs around him kept them by the thousands. He had walked through a market in the highlands of central Mexico that stretched farther than any he had seen in Europe. Pastels of chile and cacao and woven cloth. And now he stood before creatures the Aztecs called by a name he could not pronounce.

[00:00:30]They were everywhere in the city, fed on maze, traded as wealth, sacrificed in temples, eaten at feasts. The soldier had never seen anything like them. He assumed, as Europeans would for centuries afterward, that this was simply a strange new creature from a strange new world. He had no idea he was looking at one of the only animals the people of the Americas had ever truly tamed. He had no idea that this bird had been living alongside human beings on this continent for longer than Rome had existed. And he had no idea that within a few generations, his own descendants would carry this bird across an ocean, breed it into something new, and ship it back to the very continent it came from, never knowing they were returning a native to its homeland. We call it the turkey. It sits at the center of a holiday, roasted and carved and photographed, the most domestic of domestic birds. And for most of modern history, almost everything we believed about where it came from was wrong. We were wrong about how many times it was domesticated. We were wrong about which birds gave rise to it. We were wrong about the people who first kept it. And we were wrong most strikingly about the fate of one of its founding lineages, a lineage that no longer exists. This is what the ancient DNA actually shows. Let's begin. For a long time, the story of the turkey was barely a story at all. It was a footnote, an afterthought, a bird so familiar that no one thought to ask where it had come from. The vague assumption passed down through cookbooks and grade school history was that the turkey was a wild North American bird that early American colonists had caught, penned, and gradually tamed. The pilgrims, the first Thanksgiving, a wild bird from the New England woods brought to the table. That was the picture most people carried, and it had the comfortable feel of common sense. There was real evidence behind a more careful version of this idea. Wild turkeys were genuinely abundant across North America.

[00:02:43]From the forests of the east to the deserts of the southwest to the highlands of Mexico. Naturalists had long divided them into several subspecies. The eastern, the Mariams, the Rio Grand, the Oyola, the Goulds.

[00:02:59]Each adapted to its own region. The bird was indisputably native to the continent. So when domestic turkeys turned up in the archaeological record of the American Southwest in the great Pueblo settlements of the ancestral PBlo and people, the natural assumption was straightforward. The local wild birds, the Mariam's turkeys that still roam those landscapes today must have been the ancestors.

[00:03:26]People caught the wild birds that lived nearby, penned them, and over generations, those penned birds became the domestic flocks found in the ruins.

[00:03:35]The wild bird at the edge of the village became the tame bird inside it. It was the simplest possible explanation, and for decades, it stood. The trouble was that the simplest explanation rested on association rather than proof. A domestic turkey bone found in a Pueblo and a wild Mariam's turkey living in the hills above that same PBLO.

[00:04:03]Look like an obvious before and after, but proximity is not ancestry. No one had actually traced the genetic line from the wild birds of the region to the domestic birds in the ruins. The assumption that the local wild turkey was the founder was exactly that, an assumption built on the reasonable but untested idea that people domesticate whatever is closest at hand. And there was a second larger question that the tidy picture quietly ignored. If the turkey was domesticated in the southwest, what was its relationship to the turkeys the Spanish had found tamed by the millions in central Mexico? Were these the same event or two different stories that had been folded together because nobody had looked closely enough to tell them apart? To answer that, someone had to stop looking at where the bones were found and start reading the DNA inside them.

[00:04:58]In 2010, a team led by Camila Spellellar, working with Brian Kemp, Dongya Yang, and colleagues across several institutions, published a study in the proceedings of the National Academy of Sciences that did exactly that. The team extracted and analyzed ancient mitochondrial DNA from Turkey remains recovered across the American Southwest, bones, and even preserved droppings drawn from archaeological sites that span more than a thousand years of occupation. The samples came from across the four corners country from ancestral PBLON sites in the great drainages where PBLO culture reached its height. They compared this ancient DNA against the genetic signatures of modern wild turkey subspecies, including the Mariam's birds that live in the region today. It was the most rigorous genetic look at turkey domestication ever attempted. And it was designed to test the obvious story directly. Did the domestic turkeys of the southwest descend from the wild turkeys of the southwest? The answer was no.

[00:06:02]The domestic turkeys of the ancient southwest belong to a distinct genetic lineage, a maternal haplo group the researchers labeled H1. And that H1 lineage did not match the local Mariam's wild turkeys at all. Instead, its closest relatives were wild turkeys from much farther east. Birds genetically similar to the eastern and Rio Grand subspecies.

[00:06:26]Not the birds living in the southwest itself. The people of the southwest had not simply tamed the turkeys in their own backyard. The founding stock of their domestic flocks had come from somewhere else. A population genetically distinct from the wild birds that surrounded their villages. But here is where the story becomes strange. The same study quietly demolished a second longstanding idea. For years, some researchers had wondered whether the Mariam's wild turkey, the bird that lives across the Southwest today, might itself be a feral remnant, the escaped descendants of those ancient domestic flocks gone wild after the PBLO emptied.

[00:07:03]It was a neat thought. The modern wild bird as a ghost of the vanished domestic one. The DNA falsified it cleanly. The H1 domestic lineage and the Mariam's wild lineage were genetically separate.

[00:07:16]two distinct clades that had not given rise to one another. The wild turkeys of the southwest were not the ancestors of the domestic ones and they were not the descendants either. They were a different bird that happened to share the same desert. And here the story becomes darker because that H1 domestic lineage, the founding maternal line of one of only a handful of animals ever domesticated in the Americas, is gone.

[00:07:43]The genetic evidence showed something remarkable about how the people of the southwest managed their birds. The same H1 matroline predominated across an enormous span of time from the earliest evidence of domestication around 200 BC through the great fluoresence of PBLO culture between AD 1200 and AD 1500.

[00:08:05]For well over a thousand years across thousands of square miles of the greater southwest, a single maternal lineage of Turkey dominated the domestic flocks.

[00:08:14]That uniformity is not an accident. It is the signature of deliberate, sophisticated, sustained breeding. A population maintained and propagated by human hands across more than a millennium and traded between communities over vast distances. These were not casually penned wild birds.

[00:08:33]This was a managed domestic animal bred true for longer than most civilizations last. We can see the texture of that management in the ground itself. At sites across the Colorado Plateau, archaeologists have found dedicated turkey pens, layers of compacted droppings thick enough to be excavated as distinct deposits and the small bones of birds that died young alongside the eggshell of birds that were hatched and raised in place. Whole turkeys were buried with apparent care. Some wrapped, some interred beneath floors and in the fill of abandoned rooms. A treatment that speaks to a relationship closer than livestock. The penning, the hatching, the burials, the sheer volume of accumulated dung all point the same direction. People were not occasionally trapping a wild bird. They were running flocks generation after generation and keeping the line intact. The DNA cannot tell us exactly why they kept these birds, but the archaeology and the bones together tell us it was not at first mainly for meat. The turkeys of the Southwest were prized for their feathers used in blankets and robes and ritual and for their bones worked into tools. A single feather blanket could consume thousands of feathers plucked from living birds over many molings, which meant a household needed a standing flock kept alive for years rather than killed for the pot. The hollow leg bones became alls and needles and the tubes of beads and whistles. The birds were woven almost literally into the material and spiritual fabric of Pueblo life. And then in the centuries after European contact, as the old PBLO systems collapsed under drought, upheaval, and the arrival of new diseases and new peoples, the domestic turkey of the Southwest dwindled and died out. The H1 lineage that had been bred continuously for over a thousand years simply stopped. Today, there is no trace left of this domestic breed as a living animal. It survives only as DNA extracted from old bones. One of the two great turkey domestications in human history produced a lineage that no longer walks the earth because there were two. This is the part that overturns the textbook most completely.

[00:10:51]The turkey was not domesticated once. It was domesticated independently in two separate regions by two different peoples from two different wild source populations. The Spellellar study and the broader body of genetic and archaeological work make the picture clear. In the American Southwest, the ancestral Pueblo and peoples domesticated turkeys from that eastern derived H1 stock. And far to the south in the highlands of central and southern Mexico, an entirely separate domestication was underway, carried out by the ancestors of the Aztecs and the peoples before them. Two domestications geographically distinct, genetically distinct, each occurring more than 2,000 years ago. Each independent of the other despite the long history of cultural exchange that connected Meso America to the lands north of it. The southern domestication is the one that matters most for the bird on the modern table, and its origin is its own quiet revelation. The turkeys of central Mexico did not descend from any of the familiar wild subspecies that hunters know today. They came from a sixth far less famous subspecies, the south Mexican turkey. This is a bird that barely appears in the standard accounts.

[00:12:05]The usual list of wild turkeys names five subspecies. The eastern, marryiams, Rio Grand, Oyola, and Goulds. The sixth, the South Mexican bird, is rarely mentioned, and when it is, it is mentioned briefly and uneasily because its status is uncertain in the most unsettling way. It is the smallest of the subspecies and the only one that is not in the strict sense a North American animal of the temperate zone living instead in the highland valleys where Misoamerican civilization arose. Some sources describe it as critically endangered. Others conclude that as a truly wild animal, it is already extinct, its former range now holding only scattered sightings that may be domestic birds or reintroductions of other subspecies.

[00:12:56]The wild progenitor of the world's domestic turkey may itself no longer exist in the wild. A landmark genetic study in 2010 was what definitively sorted these lineages out, establishing that all of our modern domestic turkeys trace back to the tamed birds of southern Mexico and that those birds in turn descend from the southx wild subspecies.

[00:13:21]Later work, including a 2018 study by Gabriella Padilla Hakobo and colleagues published in Genetic Selection Evolution, continued to probe the evolutionary history of Mexican domesticated and wild melagorous galopavo, refining the picture of how the wild birds of Mexico gave rise to the tame ones. The thread that runs through all of it is the same. The domestic turkey of today is the descendant of a Mesoamerican bird whose wild ancestor has faded almost to a ghost. The DNA cannot tell us precisely when the first wild turkey in Mexico stepped permanently into human company.

[00:14:00]It can only tell us that the process was already underway more than 2,000 years ago and that it followed a pattern we have seen with other animals lured into domestication. The turkeys came for the maze. As people across both regions settled into permanent villages and built their lives around stored grain, they created exactly the conditions a foraging bird finds irresistible.

[00:14:23]A field of ripening maze, a midden of discarded scraps, a granary that leaks a steady scatter of kernels onto the ground. These are a standing invitation to a large ground bird that will eat almost anything. The boldest birds, the ones least frightened of people, ate best and lingered longest. And over generations, the distance between the flock and the village closed on its own.

[00:14:49]Researchers studying the chemistry of ancient turkey bones, including the archaeologist Aaron Thornton, have looked precisely for the moment when the diet of turkeys begins to converge with the diet of humans. the point where the birds stop eating wild forage and start eating the maze that people grew and fed them. The carbon signature of maize, a plant with an unusual photosynthetic chemistry, leaves a distinctive mark in the bones of anything that eats it. And as that mark deepens in the turkey bones, it tracks the bird's passage out of the wild and into the human fold.

[00:15:22]That convergence marks the threshold of domestication, the moment the bird's world became the human world. settled life and stored grain drew the turkey in in the southwest and in Mexico alike.

[00:15:35]Two separate peoples reaching the same arrangement with the same kind of bird.

[00:15:40]It is worth pausing on what the turkey represents because its singularity is easy to miss under the weight of its familiarity.

[00:15:48]The turkey is the only vertebrate animal domesticated in North America in ancient times. In the great centers of the old world, people domesticated a long roster of creatures. Cattle, sheep, goats, pigs, horses, chickens, and donkeys. In the Americas, the list of domesticated animals is short. The llama and alpaca in the Andes, the guinea pig, the muskavy duck, the dog carried in from elsewhere long before and across the entire vast expanse of North America.

[00:16:19]The turkey stands essentially alone as the one native bird or beast that ancient peoples bred and kept.

[00:16:28]Everything that the dog, the cow, the horse, and the chicken meant to the human story of the old world. The turkey carried almost by itself in the new. It is not a minor bird. It is one of the most significant domestication events in the history of the hemisphere. and it happened twice.

[00:16:51]Then came the collision of two worlds and the strangest chapter in the bird's history began. When the Spanish reached central Mexico in the early 16th century and found these tame birds kept in abundance, they did what conquerors do with valuable things. They carried them home. The Aztec turkeys crossed the Atlantic to Spain and from there spread across Europe with remarkable speed, becoming an established domestic fowl in a matter of decades. By the middle of the 16th century, the bird had reached England, and within a generation, it had become common enough on European tables to lose any aura of the exotic.

[00:17:32]Europeans, never quite sure what to call the new bird, gave it a tangle of confused names. They associated it with exotic trade routes and faraway lands.

[00:17:43]And through a chain of linguistic accidents, English speakers came to call it the Turkey after a country it had nothing to do with on the assumption that anything strange and imported must have come through the Eastern Mediterranean. The French called it the bird of India, the Indian chicken, equally lost, gesturing at the wrong continent entirely. The bird carried the name of a place it had never seen. In language after language, a small monument to how completely its true origin had been forgotten even as it spread.

[00:18:21]And then the loop closed in a way no one intended. European colonists sailing west to settle the eastern coast of North America brought their domestic turkeys with them. The descendants of the Aztec birds that Spain had carried east. So the barnyard turkey arrived in North America from Europe, a domestic animal imported by settlers, even as wild turkeys.

[00:18:54]and the memory of the vanished southwestern domestic flocks were already native to the continent. The bird had been domesticated in the Americas, shipped to the old world, transformed there, and shipped back, returning as a foreign import to the land that had created it. The turkey on the first colonial farms was an immigrant whose ancestors had never left the hemisphere. The transformation did not stop. Over the centuries that followed and with brutal acceleration in the modern era, the transformation of the turkey continued. The lean, fast tree roosting birds of the Mexican highlands, and the eastern forests were reshaped by selective breeding into the broad- breasted commercial turkey of the modern farm. An animal grown so large and so heavily muscled that the standard industrial breed can no longer mate naturally and must be reproduced by artificial means. A wild turkey can run, fly into the canopy to roost and outpace most things that chase it. The broad- breasted white that fills a supermarket freezer can do almost none of this. Its body weighted so far forward over its chest that the simple mechanics of reproduction have become impossible without human intervention. The bird that the Aztecs fed on maze and the puebloans bred for its feathers became a creature engineered almost entirely for the volume of meat on its chest raised by the hundreds of millions. Its body so far from its origins that it cannot reproduce itself without human hands at every step. The plump white barnyard fowl is in a sense the final ghost of the south Mexican turkey. Its wild ancestor faded toward extinction while its domesticated form multiplied beyond counting. What does this mean for the turkey sitting at the center of the table right now? It means that the most ordinary of birds carries one of the most extraordinary and least known origin stories of any animal humans have ever kept. It was domesticated not once but twice independently by two ancient American peoples more than 2,000 years ago from two different wild lineages.

[00:21:13]Neither of which is the bird most people would guess. One of those founding lineages bred continuously for over a millennium in the pueblo of the southwest is gone surviving only as DNA and old bones.

[00:21:28]The wild ancestor of the other, the South Mexican turkey that gave rise to every bird on on every modern farm, has itself faded close to extinction in the wild. The turkey is the only animal of its kind domesticated in ancient North America. A singular achievement folded so completely into the everyday that we forgot it was remarkable at all. The bird on the table is not a tamed wild creature caught by colonists in a New England wood. It is the descendant of an Aztec domestic animal that crossed an ocean, was reshaped in Europe, and was carried back across the same ocean to a homeland it had never lost. It is ancient and strange and twice made. And it carries inside it the memory of peoples and birds that no longer exist.

[00:22:18]400 years ago in a market in central Mexico, a Spanish soldier looked at a cage of dark iridescent birds and saw something new. We do not know his name.

[00:22:30]We do not know what he was thinking.

[00:22:33]But the birds he could not name were older companions of humankind than anything he had left behind in Europe.

[00:22:39]And their descendants would outlast the empire he served, multiplying across the world. While the wild birds that began the whole story slipped quietly toward the edge of existence.

[00:22:51]If you found this story remarkable, consider subscribing. There are more origins to uncover, and the DNA is only beginning to tell us what it knows.