you're watching national geographic channel presents there's a place so ghastly and grotesque that most people recoil in horror but these acres filled with decaying human flesh actually save lives this is a training ground for forensic specialists solving murders one corpse at a time unlocking the secrets of the body farm [Music] [Music] a skeleton uncovered in memphis maybe we can find a grease spot where the actual body decomposed a family murdered in mississippi a body stashed in a las vegas locker real crimes with real consequences we've got a rib we've got a bright scapula what's the connection between these grizzly discoveries real csi scientists turned crime scene investigators dramatized on a hit tv series but what do they really do did the skull look small to you too ready can you go up to him and where do they learn their trade welcome to ground zero in the field of forensic anthropology a unique outdoor classroom where the subject is deaf more than half the csi units working in the us today have been trained founded by dr bill bass of the university of tennessee more than 25 years ago research conducted within these few wooded acres in knoxville has redefined the frontiers of forensic science the anthropology research facility what most people call the body farm is a research facility that i set up to begin to look at the decay and the rates of decay in human bodies like many anthropologists bass started out studying ancient bones his expertise eventually led to his helping the police with modern day murder victims you know we kill our friends and neighbors by many different means but a lot of people are shot or are bludgeoned or stabbed my orientation was what happens to a body when it decays and how long does it take he learned to read bones for signs of trauma knife marks and ribs unusual fractures in skulls drawing on unclaimed bodies from county morgues he built an extensive collection of skeletons [Music] but early in his career bass realized that bones weren't the only source of clues decomposing flesh had secrets to reveal as well i got a call one afternoon it was between christmas and new year's was cold from the wildest county sheriff's office telling me that they had a grave that had been disturbed would i come and help so i get over there this is a family cemetery back of a home someone had broken into the earth near a headstone just beneath the surface a headless male corpse the remains looked fairly fresh police needed to know how fresh had a new body been added to an old grave dr bass agreed the body was in good shape pink flesh still clung to the bones i looked at it i said you have a 24 to 28 year old white male who's been dead about a year but something didn't add up bass kept digging ultimately identifying the body as colonel william shy a rebel officer killed in the civil war buried in an air-tight cast iron coffin the corpse had been incredibly well preserved bass's original assessment had been off by more than a century people wonder why i started a body farm it's because of a couple of experiences like that that make you realize that you know you really don't know much about decay rates and we need to do something about that by now more than 400 human corpses have decomposed at the body farm every phase documented under a wide range of conditions some critics say letting corpses decay here is irreverent but the scientists insist the dead are held in the highest respect it's important to remember that the anthropology department the forensic center doesn't own these bodies they're a gift to us to study decomposition but if the day comes and families ever decide that they want them they belong to them i always try and take a minute and say thank you because without them we wouldn't be able to do any of this research and this place would not exist there's no doubt that the work done here is incredibly valuable resulting in the convictions of countless violent criminals who may have otherwise walked free and those bodies so generously donated are put to good use in earnest efforts to protect the living we've looked at decaying bodies in various scenarios clothing no clothing sun shade buried not buried water trunks of cars we've been able to establish a sequence of events that occurs under all of these conditions you can see here all through here where it's all decade we got some more buzz forensic anthropology and forensic entomology really take off from right here where we're walking i mean this is in a sense ground zero where this particular research uh takes place it's interesting because i say okay dr murray marks is one of the thousands who have studied at the facility now he's on the faculty guiding the research of a new generation of scientists when i see remains like this i'm always reminded that this is such a unique laboratory because where else can we study this whole process of decomposition we're there to speak for the victim for the people that don't have a voice by doing that we get ever closer to the truth and ever closer to making someone pay for their crime the body farm's many successes have spread the facility's influence far and wide a new program called the national forensic academy allows police and lab technicians from throughout the united states to hone their skills amid a cornucopia of fresh bodies decomposing corpses and overgrown skeletons if at any time you have a problem i strongly recommend you turn around and take a deep breath okay it is not a pleasant thing it is something that you have to face at some point in your careers in a wooded corner of the facility the scientists have scattered a mixture of human bones animal bones bullet casings and other simulated evidence stained by time soil and weather and hidden by leaves the scattered bones are difficult to find just as they would be at an actual crime scene sorting through human remains can be an unsettling task even for professionals sometimes that whiff is just too much next how to find a murder victim when the body is already buried six feet under national geographic channel presents we'll be right back now back to national geographic channel presents the secrets of the body farm aren't reserved solely for human students most cadaver dogs are trained to find corpses with synthetic samples that smell like decay here dogs are able to practice on multiple human bodies in varying states of decomposition what you got you find something they're taught to lie down or bark when they find human remains oh good girl what you got show me good girl you ready you want to find some more finding corpses on the surface is just a warm up the dogs move on to a series of concrete slabs for the graduate course under the yellow arrows a researcher has buried corpses and other debris [Music] very good success is rewarded immediately to reinforce every dog's complete attention to the task jane survey is in the early stages of training her dog to indicate a discovery find it while there's such overwhelming sense we want them to concentrate and indicate on everyone they find what can happen especially in early stages of training in something like this is that they would go from one source to another source to another source without indicating this is a great opportunity because it tells them every single one indicate immediately then go on to the next you did very good you're a smart dog find it if you saw her head glory show me no you show me yeah good dog when she got over here her breathing changes and if you watch them very closely you can tell that it's almost like they inhale and then they stop breathing because they're processing the scent good dog are you the smartest girl even the best cadaver dogs can have a difficult time locating some corpses the body farm is the perfect lab for developing new technologies that can help locate human remains we have a problem in the united states of the husband and wife one of them gets gets mad kills the other one they take him out in the backyard and bury him then they pour a concrete slab over them and it's hard to find this is an experimental ground penetrating radar system gprx on loan from the u.s government it's one of only two units of this gpr model in the world it's been developed to locate dinosaur bones find unexploded artillery shells and reveal hidden bodies the system is about the size and weight of a weed whacker but it's packed with powerful electronics beneath these concrete pads at the anthropology research facility lie seven human bodies michelle miller buried the bodies at depths ranging from one foot to six feet what would a body look like at each depth could the radar see through cement and would a body under cement look different from a body under dirt i want to see the difference between cement and actual just the clay the head of one individual is right here and the head of the other individuals right there and hopefully i'll be able to see the definite difference of the gtr shooting through the cement versus the announcement miller didn't stop there she added other variables could the system distinguish between a fresh corpse and a bare skeleton or between a body and rubble i want to see if it could really differentiate you know between a definite individual and none what i did is i buried one individual on this side of the pad on the other side of the pad i actually made a mock-up i used plastic buckets metal buckets two by fours and metal tubing and actually built a body what we're trying to do is to match a situation like you're getting in tourist attacks now where you get not only the people being blown up but you get all the the building or the surroundings filled in with them can you distinguish a body under all of that what you might call noise if you want to say that or something that's confusing the picture the system's field display shows little detail just a series of swirls and squiggles representing different densities miller wants to know if those patterns can be read as bodies back at the lab the data is downloaded into a more sophisticated computer to enhance the display the display shows a cross-section cutaway of the earth a red bend across the top shows the concrete dense but transparent as a window pane to the gprx beneath that disturbed soil which yields uniform signals of green then two feet down the signals go crazy matching the size and shape of the body hidden there [Music] once a body's been found the detective work truly begins the one piece of evidence everyone wants time since death the police don't ask you who is that they ask you how long have they been there now i didn't have any experience with maggots so i looked in literature and there was very little in the literature so i decided this is an area that we needed to do research on we need to find out what happens in the decay stages of human individuals in the 1980s bass and a graduate student began charting the order and the timing of insect activity in corpses most numerous were blow flies iridescent flies that could sniff out a body within seconds each female blowfly laid eggs by the hundreds usually in natural body openings or bloody wounds in summertime the eggs could hatch in just two hours the resulting larva maggots soon formed a writhing flesh-eating mass the maggots were nourished to maturity by the proteins and lipids in the flesh some two weeks later they formed pupa casings or cocoons a few days later a new generation of adult flies emerged from those pupa casings and the cycle began anew other insects joined the postmortem food chain yellowjackets fed on blowfly eggs and beetles nibbled cartilage off bones [Music] but the key players were blowflies and their magnets then we can go to the proper uh chart the studies provided crucial data to scientists like neil haskell a forensic entomologist who teaches at st joseph's college in indiana he also testifies in murder trials coming up a brutal and mysterious murder of a young family could insect activity crack the case find out when secrets of the body farm continues you're watching national geographic channel presents [Music] the expert testimony of forensic entomologist neil haskell trained at the body farm proved crucial as a grizzly case unfolded in las vegas nevada people renting storage space in a mini warehouse had noticed a nasty smell adjacent neighbors that had their storage and they're they're complaining to the management something really stinks around here and it's time to get to the bottom of it well they got a warrant to investigate and then open the the storage unit up found the garbage can in there popped it open and here is a absolutely disgustingly decomposing individual the body mostly liquefied was an elderly woman her daughter had rented the storage unit two years before the daughter told police her mother had died unexpectedly grief stricken she stored the body while pondering funeral arrangements but haskell learned a different story from the bugs specifically from the coffin flies they're tiny about the size of gnats but they boldly go where other flies can't deep underground it's a highly evolved survival strategy underground they have a feast to themselves coffin flies got their name by their very tenacious ability to identify where humans were buried in in the wooden coffins they can burrow up to four to five feet in the soil access the coffins and then lay their eggs and they they do their life cycle there it didn't surprise haskell to find coffin flies in the container what surprised him was not finding blowflies death's quickest opportunists the blowflies can come in within the first seconds to minutes and if the temperatures are warm enough you'll see them laying eggs within the first hour but haskell found no traces of blowflies no flies no eggs no blowfly maggots [Music] the blowflies hadn't gotten to the body haskell wondered why then it hit him there wasn't time mom wasn't left laying around for a number of days mom was processed very very quickly placed in that garbage can and and put in that storage area the evidence convinced the jury that the defendant killed her mother and moved swiftly to hide the body the sentence life in prison no parole since its inception the body farm has conclusively connected insect activity with body decomposition allowing prosecutors to bring countless criminals to justice just as an archaeologist can tell how long ago a civilization ended by sifting through generations of rubble a forensic entomologist can estimate how long ago a life ended by combing through generations of insects one of the ways of determining the length of time is to gather the the maggots you want to gather the largest maggots because that indicates the first hatch and that would be a better indication of how long that individual has been has been dead up to about 14 to 21 days depending on the temperature and environmental situation in which the death occurred recently mississippi prosecutors asked dr bass to help pinpoint time since death in a brutal murder case someone had murdered a young family a husband wife and their young daughter the chief suspect a relative of the victims held a quarter million dollar life insurance policy on the child but bass was told the man had an alibi for the two weeks before the bodies were found [Music] the suspect also claimed that he tried to visit the family twice once in mid-november and again in late november so he admitted to being at the crime scene but he claimed on each occasion no one was home pinpointing the time since death was crucial i asked him to send me pictures of the crime scene send me photographs of the bodies bass looked for signs of insect activity taking into account the fact that the bodies were indoors not outside the blow flies are outside the house it takes them a few days to realize hey there's a dead body or bodies in that house how can i get in there you say finally bass spotted a key piece of photographic evidence the discarded shells that maggots leave behind as they turn into flies these pupa casings prove that once the flies finally reached the murder victims the insects underwent a complete 14-day life cycle and then some vasa's report concluded that the family was killed in november the date matching one of the defendants admitted visits to the cabin [Music] the blowflies helped prove opportunity the insurance policy provided the motive the suspect was convicted of murder it does make you feel good that you are able to look at the scientific data which is there and that's what i did i didn't know any of the people involved in this at all and from the scientific data able to make an analysis that corresponds exactly to the events that occurred in this case vasa's work proved that in cases where corpses were decomposed forensic anthropologists could make an important contribution to a murder investigation still to come when the blood's been washed away and evidence is scarce one investigator finds the answer is in the bones national geographic channel presents now continues the chronology of decomposing flesh provides csi units with useful evidence but steve sims one of the body farm's most renowned graduates focuses on what's left behind after the bugs have picked the bones cleaned here we do find a scatter five feet from somebody's foundation their house and i found the thoracic vertebra which are human over here is the skull and over here is an arm but already dogs have destroyed a lot of the ends of the bones originally sims planned for a career in archaeology after one class at the forensic facility he left archaeology in the dust this is the right tenth rib right here and right here i see some trauma indicative of shock trauma or a nice stab wound today he's taking bone trauma analysis to a new level [Music] one of the ways of killing an individual and trying to mask the identity of that individual is to saw the body up i saw the arms off so the head off [Music] sims specialty is reading signatures the telltale signs that saws leave behind when a killer cuts up a corpse i've seen everything used from knives to axes to serrated knives being used as a saw i've seen power tools used i've seen a band saw to cut up a body i've seen circular saws used numerous times bone is an engineering marble it's a composite material a flexible matrix of collagen fibers infused with calcium phosphate for stiffness and load bearing it's like steel reinforced concrete but lighter and stronger [Music] it's a durable material so the marks a saw leaves as it cuts up a body can endure for years sims took up his grizzly specialty after a detective asked him to identify a notch in a bone i said it's a saw mark on an arm bone and when i said it's a song arc i thought i was proud to give him some information he looked at me said but i already know it's a saw mark you're the bone doc what kind of saw is this and i didn't know sims needed to know it was his third dismemberment case in just one month [Music] he set out to fill this gruesome gap in forensic knowledge [Music] it would take him 15 years of research to the naked eye all saw marks look alike [Music] it turns out that's not true every tooth leaves another mark and the reciprocating action of these teeth or continuous motion of these teeth leaves lots of indicators of tool marks lots of characteristics and with enough characteristics many times i can get for example a number of teeth per inch in a tool used to dismember a body now sims can read a saw mark the way a handwriting expert can dissect a signature he can even spot false starts or skips in the stroke and he can tell police what kind of saw to search for in a dismemberment case you want to know more than a saw you want to know what kind of saw how wide that saw is how wide the blade is how wide the tooth is the minimum curve width the number of teeth per inch and how that saw was used to dismember a victim all saws look similar or look identical they really aren't a killer may think that washing blood off a blade is enough to cover his tracks but not if sims is on the case if you listed five people in the world who were the world's leaders this steve would be one of those five like fingerprints footprints and tire tracks tool marks can crack a case even years after the crime bone trauma is a moment frozen in time all the soft tissues and so on disappear or change or deteriorate with time bone doesn't change or deteriorate we just clean it up it's there it's good evidence it's evidence you can take the cord the process of normal body decomposition and bone trauma are well documented at the body farm [Music] but some killers try to cover their tracks with fire not long ago burned bones marked a dead end fingerprints faces wounds all gone burned away but the tennessee scientists were confident other evidence could be sifted from the ashes okay i bet that fits right there to know what to look for though they'd have to learn precisely what happens when fire meets human flesh and bone what i'm about to do is i'm going to build several little contain systems they're just right now i'm just testing for heat elaine pope a phd student got these body parts from an anatomical laboratory to which corpses had been willed or donated for medical research before these limbs were provided to her they were used by medical students to practice surgical procedures she starts with an arm and i'm going to photograph it before i place it in the fire i'm going to do each element that way and document what it looks like before including the size the shape and the position of it during daylight smoke obscures the details not so much from the eyes as from the camera lens so pope experiments and photographs at night [Music] as the arm heats it actually begins to move what i want to do is see how the arm draws up and how it reacts to heat when the arms react to heat they go into the pugilistic posture which is where the muscles of the arm the flexors pull the arm into flexion like this and so i want to observe that process as it occurs as muscles burn their fibers shrivel and contract the stronger muscles usually the flexors overpower the weaker ones the extensors in fact the arm's flexing is so consistent that if a body is found with the arms extended it could be a sign of foul play the body will assume that futuristic pose at all costs unless stopped from doing it the muscles are very strong and it pulls you into that pose so if i see something that goes against this pose i'm suspicious the arm was outstretched and it wasn't able to assume the pugilistic posture with the elbow that would possibly indicate that the arms had been tied even if there's an absence of the actual material they could have used string or rope which would have burned away but is that movement the same in an accidental house fire as it is in an intentional fire made hotter by accelerants like gasoline i'm gonna do the slow burn so that we can watch the gradual progression of it and then the other arm i'm gonna do in a really fast and hot and intense fire and will the arm hold its position even after all organic matter has burned away [Music] as you can see the arm has reacted as we expected it drew into the pugilistic posture with this being the elbow here and this being the wrist here and these being the hands [Music] the main torso despite the separation of its limbs will also yield clues does a dismembered body still seek the pugilistic posture i'm mainly interested in this one because it still has a portion of the humerus and the femur attached and so i'm wanting to see if it reacts the same way as if the arm was still attached to see if it's going to be drawn up and if the femur gets kind of drawn up even stumps of limbs still try to assume a fighting stance we're trying to establish normal patterns of burning that way we can look for unusual cases if a burn pattern is disrupted it could be indicative of pre-existing trauma or dismemberment [Music] some researchers including pope have done studies with animal limbs but when a murder case hangs in the balance there's no substitute for the real thing the reason why we use human material is to accurately simulate house fires and vehicular fires for one thing it stands up it's more credible in court to say yes we've tested this and we know exactly what happens it helps with the medical examiner and their testimony there are many variables to explore can decomposing muscles still flex an arm at what temperature does flesh ignite [Music] after burning the specimens pope gathers up the charred bones cleans them and studies the patterns she notes color changes in transition zones where protected unburned bones give way to charred material [Music] to fully grasp the patterns she makes detailed drawings [Music] one clear difference is fracture patterns [Music] another is calcination transformation of dense bone into a light chalky material i burn these two different tibia at different temperatures in different times and durations this one is more calcine it's burned to a further extent and you can see it has a higher frequency of fracture patterns whereas this one was burned to a lower temperature and less amount of time and it took on more of the the charred the blackness do fracture patterns change when a stream of cold water from a fire hose hits hot bone what patterns might be left when accelerants are used to heat up a fire and hide evidence of murder there's so much to be learned from bone even after fire but only time and research will tell just how much evidence can survive in the body farms quest to identify unknown crime victims new technologies meet old-fashioned techniques head on joanna hughes is a forensic sculptor putting clay on skulls she reconstructs human faces hughes hopes her work can someday help id a murder victim and catch a killer the technique employed by hughes is not only time consuming but its ultimate success hinges on a high degree of artistic talent if you are off by even a millimeter then you run the risk of having an incorrect or an unidentified individual and for every unidentified individual there is a criminal perpetrator murderer walking the streets to do a good facial reconstruction of an individual you have to have a lot of artistic ability you have to be able to get the face so it has some expression on the face so it looks like a face i've done this before and my heads look like clay heads this head looks human it also looks remarkably like the actual subject a man who donated his body to the forensic facility hughes did this reconstruction for practice then checked her work against the photos ah it's but what if she'd guessed wrong about the size of the nose or the fleshiness of the jowls in a real murder case the stakes are high and time is precious clay reconstruction yields a single guess about a victim's looks one mistake could stall an investigation [Music] murray marx hopes to overcome those shortcomings by bringing facial reconstruction into the computer age for help mark has joined forces with oak ridge national laboratory the government research lab has super computers and imaging experts marx has cranial dimensions from some 1 000 modern skulls the largest database of its kind in the world but to build a face from a skull he needs to know more about the intimate marriage of skin and bone that requires state-of-the-art mri and cat scan expertise some of the world's leaders in this field work in the research imaging center at the university of texas health science center the center's director dr peter fox is intrigued by the facial reconstruction project [Music] to provide baseline images from a known individual he's offered his scanners and his own flesh and bone fox's mri maps the surface of his face his cat scan yields a 3d image of the skull beneath the skin now the challenge is to recreate by computer a face that looks like the living dr fox if they can figure out how to do it with a known face they're optimistic they can do it with an unknown one a wireframe model helps translate the relationship between fox's face and his skull into mathematical formulas those formulas can then be used to create a facial mask in this case a mask of fox's face once the software development is complete police or witnesses could easily modify such masks what if they were heavier what if they were lighter change that hairline change the eye color or you know add a beard add a mustache things like this [Music] the tennessee scientists are taking promising steps toward one of the final frontiers in forensic anthropology to restore a face and with it the identity and humanity of a victim the conclusion of secrets of the body farm next and now the conclusion of secrets of the body farm in the early years the research conducted at the anthropology research facility was not widely known but then its unofficial nickname coined by police and fbi agents became the title of a best-selling crime novel by patricia cornwell the body farm hit the mainstream more books movies and hit tv shows followed raising the facility's profile and communicating the importance of its work the drill is that we are going to pull him out of the truck all right i'm ready this upper body's gonna drop yet you have the strength yep [Music] here death marks not an end but a beginning the start of an amazing odyssey carefully observed and recorded in my new detail by researchers robin miller is studying a specific component in human decomposition a possible linkage between clothing and the rate of decay lift his legs up and put one leg at a time and through here and then hold his legs up while someone else pulls it over his um half of all cases that we work on in the united states are people that we have found with clothing on them so my research hopes to answer the question well can we use that data in order to determine a time since death this corpse donated by family per the dead man's wishes will prove invaluable in miller's research to protect his identity he is now known simply as corpse 3101 but anonymity can't diminish his generous nature or his willingness to help others even after his death his contribution reaches far beyond pure science it may influence real-world murder cases and help bring killers to justice drawing on prior research miller has divided decomposition into four stages stage one spans the first day or so after death stage one is where is what we call the fresh stage where there is no maggot activity we just have the basic rigor al gore and liver mortis stage one is marked by stiffening discoloration then relaxation as we get out of stage one into stage two is when the blowflies come in and start to lay their eggs and their eggs will of course hatch into maggots the maggots will take over and start consuming the body stage two includes a flurry of insect activity yellow jackets flow flies and maggots the eggs that were laid a couple days ago and the nose have hatched so we have a maggot mask that's going to work around his nostrils and in his right ear and near his right eye they've eaten away on the inside of the mouth i can see some eggs that have been laid on the tongue and then the left cheek area the proteins and fats in human cells are a near perfect food for maggots the swarm of insects is a gruesome reminder of mortality as is the smell of decomposition inside the body the bacteria are starting to work on the internal organs [Music] as that happens gases are also released inside the body there's a process called autolysis where the cells inside burst because the ph level is disrupted [Music] some of the gases escape the corpse through natural body openings creating putrid smells gases that are trapped within distend the veins in the body a process called marbling sometimes the gases build up enough to burst a corpse's abdomen stage three is the longest phase of decomposition and is greatly influenced by the changing seasons we definitely have a decrease in maggot activity and fly activity because the larva and the eggs can't live below a certain temperature so the cold weather is having an effect on the decomposition here but the cycle does continue 52 days after the start of the experiment 3101 enters stage 4 of decomposition he is essentially mummified any remaining skin has the texture of leather and nearly all of the soft tissue is gone already it appears that clothing may have slowed the rate of decay but confirming that assumption will require a scientific review of the data in the weeks ahead [Music] a gentle hillside in tennessee unique in all the world a singular place set aside for gleaning knowledge and truth from flesh and bone the anthropological research facility here in knoxville is absolutely critical in research when it comes to assessing human death there's a lot of really cutting-edge research going on at the body farm right now it's the only research essentially uh of this type in the in the world two of them lee jantz believes the work is so important she's made an extraordinary commitment in spite of her discomfort with what she knows will follow i am a donor when i die i expect my family to honor my wishes and donate me to the anthropological research facility in the department of anthropology it is not a pleasant thought i don't like to think of what my body will go through but it's going to happen the dead remain the focus of scientific scrutiny at the body farm but the reason for the research the motivation and the inspiration will always remain the living [Music]