The truth is in the bones. Along the coastlines of Georgia and northern Florida, the native Guale people lay silent for hundreds of years, in burial mounds or in graves under the church floors of old Spanish missions. But the story of the Guale did not die. It was etched on their teeth and embedded in their bones.

Clark Larsen, professor of anthropology, interprets the teeth and the bones. Larsen is a storyteller. He admits this freely.

“Everything we talk about is in a sense a story,” he says. “The people I deal with are dead, so they’re not going to speak for themselves. But their skeletons are packed with information-their workloads, their diets, their status of health-all of it’s part of the story. My job is to put together a picture of who this person was, and a picture of who that population was.”

To tell this story, Larsen measures every hard part a person can leave. Think of the shape of a bone or a tooth-a deceptively simple design. But imagine recording that shape-its weight and length, its contours and textures, its orbits and pockmarks and scars-with a series of numbers fed into computers. This is a tedious job. But for Larsen, the story is spun from the data. So the data are gold.

He will use every tool at his disposal to mine the data, and so will his colleagues, a band of like-minded scientists who emerged from graduate school during the early eighties and found that they could not be confined within the limits of any known scientific field. So they have gone about inventing bioarcheology, a field they can make just as big as they need it to be. Larsen himself has written the inaugural text, a 474-page introduction titled Bioarcheology: Interpreting Behavior from the Human Skeleton, published last year by Cambridge University Press.

Bioarcheology, by Larsen’s definition, “is the study of the human biological component of the archeological record.” In simpler terms, he says, “We are looking at the skeletons of once-living people as if they were alive.”

To do this work, Larsen and his colleagues venture into any sort of science that might harbor the tools or the knowledge they need-not only the social sciences but the physical sciences and medicine, too. To calculate the strength of bones, they have delved into structural engineering, appropriating a technique for evaluating steel I-beams. They focus their scanning electron microscopes on the surfaces of teeth, identifying a particular fruit or seed by the pattern of tiny abrasions it left on enamel. And, using mass spectrometers, they identify foods in the chemistry of bone.

Even after we’ve been dead for centuries, we are what we ate.

“There are many kinds of food-corn, for instance-that leave a direct chemical signature on a skeleton,” Larsen says. “We can look at trace elements and isotopes of different kinds of elements and actually reconstruct what that person ate over the course of a lifetime.”

Yes, Larsen and his colleagues can spot a corn-eater by his bones. And as they reconstruct the fate of the Guale, the presence of corn is not just a clue. It’s a dead giveaway.

Travel back into prehistory, before agriculture, and long before the Spanish arrived.

The Guale, or their ancestors, were moving with the food supply, fishing and hunting, gathering wild plants. Health-wise, they lived pretty well. They drank from clean, clear-running streams. They ate a variety of tough but nutritious foods. Their teeth were straight and strong, and their skeletons rarely show signs of disease.

And then, during the 12th century, the Guale began to plant corn. With the shift from hunting and gathering to agriculture, the bones of the Guale became less strong, probably because they did not have to work as hard as their ancestors had. As living tissue, bone molds itself in response to the forces and loads it must bear.

But as their workloads decreased, the Guale retained many of their old, healthful habits. They went right on eating fish and shellfish, along with the corn. Larsen knows this because seafoods also leave their signatures in the chemistry of bone. With seafood providing good protein and iron, the Guale continued to thrive.

Until the Spanish came.

Few people realize, Larsen says, the extent to which Spain dominated coastal Georgia and Florida from the late 16th century until about 1700.

“The Spanish set up missions throughout the region and exploited the native populations as a source of labor,” he says. “That’s how they maintained their economic system in Spanish Florida. They basically forced these people to raise crops, and they used native laborers to carry materials long distances.”

When Larsen and his team looked at the skeletons from the Guale of this period, they found that the bones had grown stronger again, probably in response to the increase in labor. But stronger bones did not mean healthier bodies. Crowded together in Spanish missions throughout the region, the Guale lost their healthful way of life. The culprit was not just Spanish domination. It was agriculture, too.

“The common belief is that once people got agriculture, things became rosy, because that’s when civilization arrived,” Larsen says. “But there’s a lot of evidence, from many parts of the world, that this transition to agriculture wasn’t so good.”

Reviewing the records of populations that made the switch to agriculture, Larsen has found an almost universal increase in dental defects, iron deficiency, stress, and disease.

“The same story happens over and over again, all over the world,” he says. “Once agriculture is adopted, health declines. So the pattern that we found in coastal Georgia and northern Florida occurs globally, wherever this transition occurs.”

In regions where corn was the principal food crop, agriculture took an especially heavy toll on human health, Larsen says. The sugar in corn causes tooth decay, and a diet based on corn is notoriously poor, not only because corn lacks many essential nutrients but because it also contains phytate, a chemical that inhibits the absorption of iron.

Bad teeth and poor nutrition weren’t the only hazards of the agricultural lifestyle. As people crowded into permanent agricultural settlements, they lived with their wastes. In midden piles and shallow wells, parasites and microorganisms reproduced and spread disease, including bone infections rare among hunter-gatherers.

This was the fate of the Guale. Before the Spanish arrived, Guale agriculture had eased the workload. But under the Spanish, the Guale fed many more people than themselves, and agriculture was brutally hard. In the missions, the Guale stopped eating seafood, and many of them developed iron-deficiency anemia. Their life expectancies were in the low twenties.

Some of the most distressed skeletons in Larsen’s samples come from Amelia Island, Florida, which today is a picturesque playground of golf courses and posh resorts. For the Guale, Amelia Island was no resort. It was the site of the Santa Catalina mission, a place of suffering and deprivation. Twenty percent of the 120 skeletons found at Santa Catalina show the ravages of extreme iron-deficiency anemia, including porotic hyperostosis, in which the bone cannibalizes its own substance to create red blood cells. The anemia was probably caused not only by diet but by parasitic infections. In the teeth, Larsen finds signs that disease or starvation periodically arrested growth, engraving the record of life-threatening stress into grooves in the enamel. And in the spines and joints, he finds high frequencies of crippling osteoarthritis, the result of heavy, repetitive work.

Beginning in the late 1600s, British and allied Indians began to attack the missions, and the Spanish retreated deep into southern Florida, taking the Guale with them. With each move southward, the Guale population seems to have declined, both in number and in health. The few remaining families fled to Cuba from St. Augustine in the 1760s.

Today, bones are all that remain of the Guale of Georgia and northern Florida. There are many, many bones. Larsen’s studies have included some 3,000 skeletons, most of which were excavated and conserved by the Works Progress Administration during the 1930s. Since 1982, Larsen has helped to excavate Guale burial sites in two recently discovered Spanish missions, including the site on Amelia Island and another on St. Catherines Island, Georgia. As a collection, the 3,000 skeletons provide a detailed record of the Guale’s descent from a robust, vigorous people into a small band of refugees, weakened by hardship and disease.

“The Spanish thought they were going to come into this region and improve the health and life ways of the native populations,” Larsen says. “But in fact, just the opposite occurred.”

To reach Clark Larsen’s laboratory, you have to leave the campus, hike up Franklin Street, and descend into a gloomy, windowless basement room. This is not a good arrangement.

Larsen doesn’t complain, but the truth is, he is not so well equipped for research as he’d like to be. If he hadn’t long ago earned a place among his now-illustrious colleagues-among them Mark Teaford and Christopher Ruff of Johns Hopkins, and Margaret Schoeninger of Wisconsin-he simply wouldn’t make the team. They have the fine laboratories, the fancy hardware, the really cool toys. Larsen doesn’t. He remains in their circle because, as scientists, they have grown up together, and his ideas are central to their work. And he, after all, has now written the book.

So Larsen directs their La Florida Bioarcheology Project, conducts his research, teaches, trains a select group of graduate students, and plans for the day when he might bring his fair share of tools to the table.

To get there, he spends a good deal of time explaining why these stories based on bones should matter to those of us alive in the here and now. He explains, for instance, that impoverished populations around the world suffer many of the same maladies that doomed the Guale. And each of us, no matter how affluent, is being shaped by the forces that Larsen and his colleagues describe. Ever paid an orthodontist’s bill? We can thank our diets of soft, processed foods for a share of our bad bites and crowded teeth, Larsen says.

But even when he explains how much the dead can teach us about disease, or nutrition, or about the interplay of biology and culture and health, not everyone quite gets the point.

“Sometimes, when you talk with people in the medical community about skeletons and teeth, their eyes glaze over,” Larsen says. “They say, `Well there’s nothing we can do for them, they’re dead.’”

He laughs at this joke, but it doesn’t dissuade him. He lifts a femur the length of a twirler’s baton. “There’s a lot we can learn from these skeletons,” he says quietly, feeling the balance and heft of the bone. “When we understand their story, we’ll have a better understanding of ourselves.”