Inside the science of human decomposition
There’s this beautiful place in the mountains of North Carolina where death lives to tell a story. For people who have chosen to donate their body to science, their remains are laid out on the ground and left to decompose. Forensic anthropologists call them “human decomposition facilities,” but most people just call them “body farms.”
In this episode we’ll take you to a place few people ever get to visit while they’re alive. Guided by the director of the facility and her husband, both anthropology professors, we walk through each step of how bodies decay, and how the variables of weather, location, and even vultures can impact the state of skeletal remains. Learn how the research that comes out of observing this process can help police investigate unsolved murders and cold cases.
EPISODE 3: THE BODY FARM
DISCLAIMER: This podcast contains frank descriptions of human remains. Listener discretion is advised.
Amanda: Do you guys talk about bones a lot?
Nick Passalacqua: Mmm. Oh, I mean, we do, but I mean, I mean, probably more than the normal people, but maybe not as much as you might think.
Katie Zejdlic: It's not like we sit around at dinner with our, our, our children and talk about femur pathology or something.
Amanda: That's probably a good thing. That's probably a good thing, depending on the ages of your children.
Nick: We have a three-year-old and she's like, just like learning about death. And we're trying not to let her get too into it. Cause we're surrounded by bones and death all the time.
Amanda: For forensic anthropologists Nick Passalacqua and Katie Zejdlik, “bringing your work home” means something a lot different than it does for probably most of us.
Nick: You know, the nature of forensic science is dealing with people, that you know, probably don't want to be dead and maybe had had not so great lives or not so great deaths. And you know, it can really wear on you if you're not, you know, careful about trying to balance that.
Amanda: Nick runs the anthropology program at Western Carolina University, deep in the mountains of North Carolina. And Katie, well, she runs what they call “The Forest.”
Katie: There appears to be approximately a dozen individuals still out here in the facility laying on the surface decomposing. Um, none of them are wearing clothes, uh, and a range of, uh, ages in both males and females.
Amanda: The forest is what we colloquially call, a “body farm.” Bodies donated to science are laid out in and amongst the trees. They’re then used to study decomposition.
It’s a beautiful place, full of death. But this place, with all of its contradictions, is a place of learning.
Katie: Most of the people out here are in a state where they have lost all their organ tissue and their fluids and they have some dried out skin and are turning into skeletons.
Amanda: From WRAL Studios, this is What Remains – stories of connecting unidentified human remains to the missing and the murdered. I’m Amanda Lamb.
Today on the show – The Body Farm, where death lives to tell a story.
Katie: Hi, Amanda, this is Katie and Nick. We are out at the forensic osteology research station, “The Forest” for short, and we have parked at the main gate and we're walking up the road. It's a gravel road that is surrounded by trees, old growth trees on both sides.
Amanda: Katie and Nick agreed to record a walking audio tour of “The Forest”
The word Katie just used, osteology, means the study of the structure and function of skeletons and bones.
Katie: So we're just gonna sort of record a little bit of the walk up there and then I'll send you another short file…
Amanda: Nick runs the forensic anthropology program at Western Carolina University. His current research involves the ethics in the field.
Katie splits her time between the classroom at Western and Romania where she is helping to excavate and identify Medieval remains from cemeteries. At Western, she also runs this “body farm” - though, scientists prefer the term “human decomposition facility.”
Katie: There are, as I walk in, I'm looking up slope. It's beautiful inside here. There's a lot of greenery that has grown over the summer. Um, several younger trees, beautiful mottled sunlight coming up over the fence from the eastern rising sun behind me.
Amanda: The Forest officially opened in 2007– only the second “body farm” in the country. It’s goal is to promote education, research and hands-on learning for people in the field of forensics. Not only do they publish their research, but they allow their students and others, like investigators and medical examiners, access to the facility so they can see firsthand what happens to bodies as they decompose.
Katie: On the left is almost immediately inside the gate. Um, it's a 10 foot chain link fence with green slats that run through the chain link to provide for privacy. It's not much to see in there. It just looks like some grass, much like you'd expect a cemetery to look without the headstones.
Amanda: This first part of the facility is a 10,000 square foot enclosed area where donated remains are buried so students can study what happens to bodies that are found in the ground.
Katie: The individuals we bury won't be skeletonized for at least five years after we bury. So we have not formally excavated any of those yet.
Amanda: In a second enclosed area, bodies are laid on top of the ground to see how they decompose when they are not buried.
Katie: The other enclosure is approximately 5,000 square feet. It's on a slope of about 16 degrees. So we're on the side of a mountain. And that one, in addition to the chain link fence also has a 10 foot privacy fence within the chain link so that people can't see into it.
Amanda: The fence not only keeps out curious eyes, but for the most part it keeps out large scavengers. Coyotes, for example, have been known to drag body parts away. And while this does happen in some cases, here at The Forest, they are trying to be good stewards of the bodies that are donated to them. For that reason, they prefer to keep them somewhat protected and close.
Katie: So that they can just decompose with whatever, uh, nature, whatever scavengers can get in.
Amanda: As the couple walks and describes what they see, they report the status of the bodies like any scientist would--with cool detachment and a specific eye for detail, looking at the scientific markers that give them insight into what natural factors impact the bodies.
And I’m going to warn you, when Katie and Nick have their science hats on, they talk about all of this pretty matter-of-factly.
Katie: This individual has reached a point of both. Uh, it has dried out. So the skin is essentially, um, leather-like. It's very, very dry and not much of it remains at this point. If you can sort of, um, envision, almost, almost like a sack, not to sound insensitive, but all of the soft tissue is, is for the most part gone, the organs are gone and it is, uh, bones.
Amanda: Like I said, Western Carolina University was only the second body farm to open up in the country. The slang term “body farm” was actually coined after the book of the same name published by best-selling mystery author Patricia Cornwell in 1994. It was a work of fiction. Cornwell was inspired by a visit to the first such facility which opened at the University of Tennessee in Knoxville in 1981.
It was founded by Dr. William Bass as part of their Forensic Anthropology Center.
Katie: I always give them credit for really setting the stage.
cause when they opened that up, it was macabre, it was blasphemous. It was a horrible thing to do and they got a lot of flack for it. But, uh, people started to see the validity in that science. And by the time Dr. John Williams started the facility here, uh, the culture had changed a little bit.
Amanda: There are currently 9 body farms in the US, including the ones in North Carolina and Tennessee. They’re located at universities across the US – places with different climates and topography that give researchers a variety of information about how specific locations impact decomposition. There are also a few outside the United States, but Bass’ body farm in Tennessee was the launchpad for all these other programs worldwide.
Understanding decomposition is critical for people who are investigating a murder. They need to try and figure out how long a body has been in a particular spot. The rate of decomposition provides a major clue. And what forensic anthropologists and investigators find on and around a body often tell a story of what happened to the victim, a story that can sometimes point to a particular suspect.
Amanda: The process begins when a family member donates a person’s body to the facility. Usually this happens because people tell their families they want their bodies donated to science—often specifically to this program. Other times, the family decides to do this when someone dies suddenly.
Katie: We average, it's gone up in the last couple of years, maybe 20 individual donations a year, which is not a lot, but it's about what we can handle for the size of the university and our student workforce.
Amanda: So, why would anyone donate their corpse to a body farm? Katie says it varies:
Katie: But they're like, I just want to give somebody answers. I want to solve cold cases. I want my body used for this. I think it's absolutely important.
Amanda: And sometimes it’s cathartic for the families they leave behind.
Katie: Everything from seeing a positive outcome out of trauma. We've had individuals here who have died from suicide. Some from car accidents. Some from a drug overdose and the family's like, we just want to see something positive, come out of this.
Amanda: Other reasons include being one with nature...having what people call these days a “green burial,” returning to the earth and the furthering of scientific research in the field of forensic anthropology.
Katie: We've had individuals that call and say, hey, I just want to decompose the way mother nature intended, put me in the Blue Ridge Mountains and let her do her business. And they're excited that they're going to be eaten by vultures and visited by bugs and everything else. And some people want to like, be a part of a science that may provide closure.
Amanda: If people choose to donate their own body, they just fill out some paperwork and write it into their will. If there is no plan for a person after their death, the person’s next of kin can decide to donate their relative’s body.
Basically, the only limitation “The Forest” sets is weight-they prefer that the person not be over 250 pounds - because the heavier they are, the more difficult it is for the scientists to move them. They also won’t take bodies where the person has been diagnosed with a list of communicable diseases – that’s for the scientists’ safety.
Amanda: When Katie first became the director of The Forest, she was responsible for accepting the donated bodies. This meant she had to interact with grieving families as part of the intake process.
Katie: I would hang up the phone from crying with somebody, or I would cry the minute I got off the phone, I'd call my mom, tell her I love her. And I would just call it an early day.
Amanda: Katie has vivid memories of a few people she accepted as donations before the university hired a curator to be the go-between.
Katie: The second individual that I had ever accepted under my directorship, he was an adult. He was 49 years old and he had been hit by a train.
Amanda: Katie didn’t know if the man’s encounter with a train was an accident or suicide. She didn’t feel comfortable asking his father, the person she was talking to as part of the donation process. Understandably, she was dealing with someone who was experiencing profound grief.
Katie: I spoke with his father several times. And I think that's what got to me first was that this was a parent who had successfully raised a child to adulthood, and barely managing my three-year-old some days, I think that is an incredible accomplishment. Uh, and he called her and asked, is my son contributing to your science? Are you learning something from him? And I think it was a way for it to help him process his grief.
Amanda: Another case that sticks out for Katie is that of a young woman in her twenties.
Like the father in the first case, what the mother of this young woman really wanted to know was not what would happen to her daughter’s body, but if what the scientists would learn would make her daughter’s life more valuable.
Katie: That was one where I definitely cried on the phone because I just thought I had, at that time had just had a baby, my first and thought, wow. Um, and that was another one where, uh, they wanted, they wanted to know that this death wasn't just all loss, that things would be learned and relearned and everything…yeah.
Amanda: Once the body farm gets someone’s corpse, the emotional hats come off, and the scientific hats go on. Mostly...
Katie: There's definitely been a couple out there when I've gone out to collect data or to take a picture. And I just think I am so sorry. You know, I'm so sorry that you got hit by the car that you had to end your life or that cancer took you. And so you can't always separate it.
Amanda: Katie says it’s a tricky balancing act between the need to be human and respectful, and at the same time, the need to put your emotions aside and focus on the science. A lot of the people we talked to in this line of work feel the same way, there’s a fine line.
Katie: Cause when the human is part of it, and they're always a part of it. Um, it's hard to separate it, but when you can sort of move into science mode and there's, there's a different goal there. Like, I'm going to collect all the data I can. I'm going to take the best care of this individual that I can cause they've given us an incredible irreplaceable, generous gift.
Amanda: After the break, the tour continues as Katie and Nick explain what everyone can learn from decomposing bodies.
Amanda: There are many ways a person’s remains might end up at The Forest, but once they’re there, it’s ultimately the science Katie Zejdlik and Nick Passalacqua are after. So when they get a body, they start by laying it out on the ground inside those privacy fences.
Katie: They'll take some basic photos to begin with. What did the body look like when it arrived? Um, some individuals have only been dead for a couple of days. Sometimes an individual has been dead--we've taken them depending on the level of decomposition. Um, individuals have been dead for as long as two weeks. It really depends on if they've started to decompose and how they've been maintained in the interim.
Amanda: There’s nothing fancy about what they do according to Katie and Nick, they simply put the bodies outside and let nature and small scavengers take over. They document the bodies throughout the different steps of decomposition. They record things like how long it takes for someone’s fluids to drain, for their skin to fall away, what happens to their hair, their nails. They also document the weather: temperature and humidity.
Katie: We lay them out and we just take pictures of what mother nature does to them.
Amanda: There are basically five stages of decomposition. The first one is when the body is fresh, still unaffected by its environment. The second one is when the body bloats, filling up with fluid and gases. In this stage, the body’s own bacteria start feeding on the soft tissue. This is also when the flies arrive, laying eggs that will eventually hatch into maggots.
The third stage involves the beginning of tissue decomposition aided by the bacteria and the insects. In this stage the body loses its fluids and begins to shrivel to skin and bones. In the fourth stage, which is advanced tissue decomposition, the skin begins to fall away, which can take up to six months. The fifth is when the body becomes skeletonized.
Scientists take measurements of the body as it goes through all of these stages to record what each one looks like along with photographs.
Nick: Decomposition is really like the breaking down of something into its more simpler forms. So basically everything decomposes, it really just depends on the timeline that we're talking about.
Amanda: They also track the microbes in the body. These are organisms we can’t see, but they’re present in almost every living thing including our bodies. In a decomposing body, they attract scavengers and insects. By studying these microbes, scientists can tell with pretty good accuracy how long a decomposed body has been in a certain spot.
Nick: The type of environment that the body's in or what happens to it will make it decompose at faster or slower rates.
Amanda: Ultimately, that’s the goal - to teach forensic anthropologists and investigators how long victims have been in a specific location based on their level of decomposition, and what’s happened to them while they’ve been there.
Katie: Ideally someone goes missing in the North Carolina mountains or in the woods and we can see a level of decomposition, we kind of have an idea of what we're looking for based on temperature, humidity, even slope. You know, we're starting to notice that the same bones can roll if we don't sort of put them in a specific way.
Nick: So you can learn things like how likely is it to find an arm this far from a body or that far from a body? You know, how likely, how, how far did this coyote probably drag this thing? Or what direction did it probably drag it? If we're missing a skull and we're on a slope, right? Like how, how far did it probably roll?
Amanda: As they give us a tour, Katie describes how one body she comes across is affected by multiple factors at one time. Part of the science is understanding how everything from weather to the soil to the topography to wildlife play a role in decomposition.
Katie: The legs have been displaced off to the side. This can be, um, a result of some of the scavengers that come in. It can also just simply be a result of all the rain that we've had in Western, North Carolina over the last several months, and also being on a slope.
Amanda: And remember how those fences around the facility keep out the really big scavengers? They don’t keep everything out. One of the major developments from research here at The Forest has been understanding the patterns of vultures. Unlike other scavengers, vultures don’t devour a body all at once, but over a period of days and weeks.
Katie: Immediately, as I walked to the gate, I noticed that there is a vulture feather, right in front of me, sort of up one of the unofficial paths that we use when we walk around. The enclosure where we placed individuals.
Amanda: Katie also notices a much smaller scavenger taking over one of the bodies.
Katie: Just slightly lower than the pelvis is a whole mat of uh, maggots that are moving around and you can't hear them today. In fact, you can hear the cicadas behind me and some of the birds, but you can't hear the maggots today, but that is, um, a common sound as, as they are feeding on the individual while they decompose, so I can see them, but we cannot hear them.
Amanda: And it’s not just what scavengers do to a body, it’s what they take away.
Katie: I also see a mat of hair. That appears to be off to the left side of the individual, right about where the left hip would be. And the mat of hair is also something we started noticing with the vulture activity out here. We think they're collecting hair for nests because our curator saw one of these mats of hair fall from a tree in front of her while she was out here. And it appears to be hair from various donors.
Amanda: Knowing this kind of thing gives investigators a better idea of how far out from the body they need to search for evidence that may help them identify someone.
Generally, how it works is that law enforcement puts up crime scene tape around a body, and they search within the scope of that tape. But often evidence lies outside the tape, especially if scavengers have dragged part of a person’s body or something on the body away from the crime scene, like a piece of clothing, jewelry or hair.
Every piece of evidence is important and even the tiniest details can help investigators determine who the person is and who the person is not. And the research coming out of The Forest, aims to make police more effective in this process.
Nick: Pictures can document a lot of great things. But if you only learn things from pictures, when you get into the real world, it might just be too overwhelming for you to handle.
Amanda: They do a lot of hands-on training at The Forest.
In March of 2020, Nick organized a workshop for federal, state and local firefighters with the support of the ATF, that’s the federal Bureau of Alcohol, Tobacco, and Firearms. The goal was to help them understand how to recover and examine bones that have been burned at a fire scene. Remarkably, this isn’t something many fire investigators have much, or any, training in. And it’s complex – learning how to gather the evidence without damaging it, and trying to figure out what it means to their investigations.
Officers also come to The Forest to teach their police dogs how to search for missing people. It’s practical experience they really can’t get anywhere else.
Katie: We have an internationally recognized cadaver dog training program, so we've trained human remains detection dogs out here.
Amanda: Katie says some of the breakthroughs they’ve had with dogs involve teaching them how to smell actual decomposing bodies instead of a chemical simulation, which is how it's normally done. This has also led to some research in how dogs detect human remains, even when humans can’t smell it. Dogs can smell remains 15 feet below the ground.
Amanda: And for the officers of all stripes that come here--it’s a chance to learn about decomposition in real life.
Katie: We've had officers come in and just look at different levels of decomp. Sometimes, understanding what five days in, in the middle of June looks like compared to two weeks. Sometimes, people just want to know if they can handle decomp. If they're going into these fields or as, as new officers.
Amanda: The testing of one’s mettle isn’t limited to professionals, it’s also useful in ruling students in and out of the profession of forensic anthropology.
Nick: One of our students here a couple of years ago, who was. A great student. Um, the first time that she came to our decomposition facility, she like walked in and walked right out and was like, I can't do this. Like, you know, for whatever my personal reasons, my whole life, all I've ever wanted to do is be a forensic anthropologist. And now that I'm confronted with the reality of it, I love anthropology. And it's just going to have to be a different type of anthropology that I do. Cause I just can't personally handle it, handle the reality of this.
Amanda: But one of the biggest gains the anthropology students get from the facility is the ability to study real skeletal remains once the bodies have fully decomposed.
Katie: Uh, this individual Is a male and has beautifully skeletonized remains. They are, uh, ranging in color from a light beige to a, sort of a dark dirty brown. And a lot of this is a result of them simply being dirty because they're in the dirt, but also soil staining because of the environment they're in. It's a common misconception that everyone's bones are bright white and bones will often stain to their burial environment.
Amanda: At this point in the podcast, we’ve already talked about how much bones can tell a scientist about a person – age, sex, ethnicity. But, not that many schools have a robust skeletal collection for students to learn from.
Nick: So teaching students how to do the methods that we already do or to validate or create new methods based on those remains.
Amanda: Real, well-preserved skeletons are expensive, they can run thousands of dollars and are often pretty hard to get. While there are no federal laws prohibiting the sale of human skeletal remains, other than the remains of Native Americans, there are some ethical concerns about where the bones come from and so forth. As a result, many schools use models, plastic models to teach their students.
So, Western Carolina University is in the process of developing their own bone collection. Once the bodies are fully decomposed, those skeletons are brought inside to the lab so that students can study them and learn how to figure out for themselves what these bones reveal about a person.
Katie: So in addition to the facility, documenting composition, we're also creating a known skeletal collection. Once the remains skeletonize in a facility, which takes approximately a year, depending on weather and scavengers, we bring them in, clean them up and we curate them indefinitely in our collection.
Nick: There's always tons of research coming out all the time about different ways to estimate, age, sex, different ways to estimate how tall someone was different ways to figure out, um, where someone might have been from ancestrally.
Amanda: The collection also includes animal remains.
Katie: That's another component of what we do is animal remains compared to human remains. Another really important piece for people to learn, including law enforcement. So, when they do find bones out in the woods, or, um, while they're doing their jobs, they can ask us, uh, if they're human or nonhuman and hopefully many of the students who come through the program should be able to identify that.
Amanda: Many students go on to work at universities – researching, teaching and helping law enforcement and medical examiners in their communities. Others work in state and federal government, for example, the US Department of Defense employs forensic anthropologists to identify prisoners of war and military personnel missing in action. Suffice it to say, it’s a pretty niche profession, a pretty small field populated by a group of highly skilled and focused individuals.
The knowledge they gain at a place like The Forest and with the bone collection well, it’s unparalleled.
Nick: There's no substitute for it. The gift of someone's remains as an educational tool is unparalleled. And, um, to try to learn how to do forensic anthropology, just by, you know, pictures of bodies or with plastic skeletons. You just can't do it.
Amanda: For people and families who want their bodies to have life after death, the bones become sort of a living legacy to the donors for generations to come.
Katie: Your skeleton stays here for as long as we have this program. And the skeleton would be used over and over and over again for research, for training, for reevaluating, these methods for going back 20 years from now and looking at what we thought we knew.
Amanda: And it’s that respect for human life after death and the possibilities of ongoing discovery that drive forensic anthropologists to continue developing and sharing the science that helps solve even the most difficult cases-the cases of the missing and the murdered.
Amanda: On the next episode of What Remains… a chance meeting plus a legendary cold case turns a curious 17-year-old into one of the country's most important missing persons experts:
Todd Matthews, The Doe Network: I started out with an unidentified body, so just the satisfaction to be able to unravel something that somebody tried so hard to hide at some point, that’s good. The justice in it. You know, somebody didn't get away with murder.
Amanda: This episode of What Remains was written by me, Amanda Lamb, and produced by Anita Normanly. Our executive producer was Wilson Sayre who also edited the episode with mixing from Marc Maximov. What Remains was directed by Shelly Leslie. Please subscribe to our podcast on whatever app you use. That makes it easier for us to get you the latest episode. Thanks so much for listening.