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We received our first donated body for study in May of 1981. To preserve the anonymity of the donors, I instituted a numbering system so that research reports would refer to bodies by number, not name. That first body in 1981 became body 1-81; it was soon followed by 2-81, 3-81, and 4-81. In 1982, the numbering sequence would begin with 1-82, 2-82, and so on. (The numbering system for forensic cases is similar to the system for numbering donated bodies, but in forensic cases, the year comes first: our first forensic case of 1981 was 81-1.)

The body donations came slowly at first: we relied heavily on unclaimed bodies from medical examiners around the state. Our numbers didn’t even make it out of the single digits during our early years; now, though, so many people know about our research and want to support it that we’re getting into the triple digits — well over a hundred donated bodies — every year, with donated bodies surpassing unclaimed bodies by wider and wider margins. One early and influential reason for the rising interest in our research was Patricia Cornwell’s novel The Body Farm, a blockbuster that shot up the New York Times bestseller list in the fall of 1994. Cornwell didn’t actually coin the nickname “Body Farm” (that dubious honor, as best we can tell, belongs to an FBI fingerprint expert named Ivan Futrell), but she sure did put us on the map. In the years since her book catapulted us to fame, the Body Farm has been featured in numerous television documentaries, newspaper and magazine articles, radio reports, and, in the past couple of years, a bestselling crime-fiction series, the Body Farm Novels, that Jon Jefferson and I are writing under the pen name “Jefferson Bass.” The plots and many of the characters in our novels are fictional, but the science is factual, based on more than a quarter century’s worth of experiments at the Anthropology Research Facility. As the Body Farm has grown more famous, it has also grown larger; at the moment it encompasses two or three wooded acres, enclosed within a high wooden fence. With the huge increase in body donations in recent years, however, that’s not nearly big enough. Fortunately, the university has said it wants to expand the facility by adding another eleven acres. If business keeps growing at anywhere near the current rate, though, we’ll outgrow the addition within a few years. People these days are just dying to get into the Body Farm….

Not surprisingly, when we began our research program back in the early 1980s, our experiments were designed to answer some very basic questions: How long does it take the arms to fall off? When does the skull start showing through? At what point is a body reduced to bare bone? It didn’t take rocket scientists to realize that those processes occurred much faster in summer than in winter. Fairly quickly, though, our research projects became more sophisticated, and we developed timelines and mathematical formulas that could help us estimate, with surprising accuracy, how long someone had been dead once we obtained temperature records for the days or weeks prior to the body’s discovery. The key, we learned, was “accumulated-degree-days,” or ADDs — the sum of each day’s average temperature. For example, if a body was placed at the Body Farm during the height of summer, when the temperature averaged a blistering 80 degrees each day, after ten days the body would have accumulated 800 degree-days — and would be well on its way to skeletonizing. During a ten-day stretch of brutal winter cold averaging a bone-chilling 30 degrees each day, a corpse would accumulate just 300 degree-days — and would have barely begun to bloat from the buildup of internal decomposition gases. The beauty of using ADDs to chart decomposition was that the data could be used anywhere in the world: by around 1250 to 1300 accumulated-degree-days, a body anywhere in the world would have been reduced to bare bone or bone covered with dry mummified tissue.

Then there were the bugs. One of our earliest research projects, conducted in 1981 by my graduate student Bill Rodriguez, charted the many insect species that came to feed on corpses: which bugs came, when they showed up, and how long they stayed. Perched for hours beside corpses, fending off flies that tried to lay eggs in his nose and mouth, Bill laid a cornerstone for what would soon emerge as the new specialty of forensic entomology. Today, thanks partly to Bill’s pioneering insect study at the Body Farm, crime scene technicians all over the world know to collect insect specimens from the bodies of murder victims so entomologists can determine how long those bugs have been feeding on the flesh. Since Bill’s groundbreaking insect study, numerous entomologists have come to the Body Farm, the only research facility in the world where on any given day, dozens of human corpses at every stage of decay — freshly dead, completely skeletonized, and everything in between — are there for the observing, as accessible to insects as they are to scientists.

Entomologists aren’t the only scientists who rely on the unique research opportunities the Body Farm offers. One of my former graduate students, Dr. Arpad Vass, a research scientist at Oak Ridge National Laboratory, has spent the past several years sampling and chemically analyzing the gases given off by bodies as they decay. So far, Arpad has identified more than 450 different compounds in those gases; knowing exactly what those chemicals are is allowing Arpad to develop a mechanical “nose,” an instrument he can program to sniff out clandestine graves, just as a cadaver dog can be trained to find bodies. Arpad has also used postmortem forensic chemistry, to coin an awkward term, to determine time since death: by analyzing the chemistry of death and decay products and studying how the ratios of various chemicals change as a corpse decays (just as entomologists study the changing parade of insect activity), Arpad can correlate chemistry with time, and read the decay products like a clock that has been ticking off the hours or days or weeks since death. He’s also conducting research to understand why bodies give off energy fields; his hypothesis is that the chemical reactions of decomposition turn the body into a giant biochemical battery, in effect; if that proves to be the case, it means the Energizer bunny could retain some voltage even after thumping the bucket.

One thing most people don’t realize about the forensic program at the University of Tennessee is that once a corpse has finished skeletonizing at the Body Farm, its scientific life, so to speak, has just begun. In fact, when people fill out the forms to donate their body to the Body Farm — as more than a thousand people have now signed up to do — what they’re actually agreeing to donate is their skeleton; the flesh is just the biodegradable wrapper the skeleton arrives in. On a rapidly expanding set of shelves in locked rooms beneath Neyland Stadium, UT has built the largest collection of modern known skeletons (that is, of known identity, age, sex, stature, and race) in the United States, and perhaps in the world. By mid-2007, the collection — the William M. Bass Donated Collection, it’s called — included nearly seven hundred specimens, with another skeleton being added about every three days, on the average. These specimens are a remarkable resource for training anthropologists and forensic scientists (besides our own students, the Anthropology Department helps train hundreds of crime scene and crime lab technicians every year, through the National Forensic Academy). They’re also a gold mine of data for the Forensic Anthropology Data Bank, which amasses detailed skeletal measurements from people all over the world so forensic scientists confronted with an unknown skeleton can more easily determine the race and ethnicity of the bones: European, Native American, African-American, sub-Sahara African, Pacific Islander, Australian Aborigine, Chinese, or any of dozens of other groups included in the data. The donated skeletons also form the backbone of ForDisc, a powerful computer program developed at UT by my colleague and former student Dr. Richard Jantz to determine the sex, stature, and race of unknown skeletons on the basis of a few simple skeletal measurements. (ForDisc played a pivotal role in the case detailed in Chapter 9, “Listening to the Bugs.”) During 2006 and 2007, every skeleton in the donated collection was scanned with a CT scanner. In the years to come, I expect those scans will be used for all sorts of interesting research and applied forensic science, such as the FBI’s experimental facial-reconstruction software, ReFace (described in Chapter 14, “Leoma Patterson, Part 2”).