Greatest Discoveries with Bill Nye–Medicine
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Volume II, Issue I Spring 2005 FORENSICS. 1 EARTH SCIENCE . 11 PROFILE. 2 ZOOLOGY . 12 CHEMISTRY . 3 GENERAL SCIENCE . 14 Headline Discoveries is ELEMENTRY SCIENCE . 4 REVIEWS. 15 BIOLOGY . 5-8 CROSSWORD . 16 FREE to educators. TECHNOLOGY . 10, 13 To subscribe or receive Tools for Teaching additional copies, Look for the Tools for Teaching logo for send an e-mail to practical ways to help you bring science innovations into your classroom. [email protected]. INSIDE THIS ISSUE: FISHER SCIENCE EDUCATION EADLINE DISCOVERIE H TM S MAKING SCIENCE MATTER FORENSIC FARMING ehind the employee parking lot of the are tasked with finding An example of this was seen in a case where Dr. University of Tennessee medical center the bodies, collecting Bass was asked to help determine the time of is an area surrounded by a six-foot, evidence and evaluat- death of a family of three found dead in a remote B chain-link fence topped with razor wire ing the scenes. Mississippi cabin in December 1993. There were and hidden from sightseers by a wooden privacy clear signs of a dual rate of decomposition, and fence. Passersby might wonder what precious The Process this along with the insect activity documented at commodity is protected by all this foreboding the crime scene enabled him to determine the security, and most would be very surprised to Begins family died in mid-November, a full month before find out! the bodies were "discovered" by a relative. Decomposition begins Unfortunately for the relative, that was also the For, behind the fencing and padlocks lies a little as soon as a person time period when he claimed to have visited the plot of land frequently referred to as the "Body dies. The body starts to cabin and found nothing amiss. Although he had Farm" or "The Facility." It is the University of cool as the body's sys- an alibi for the time around when the bodies Tennessee's Forensic Anthropology Facility, the tems shut down and were discovered, he didn't have one for the time only one of its kind in the world, and the research chemical changes start that they were actually killed. With this informa- done here yields something very precious— the process. When a tion and other evidence, authorities were able to ground-breaking forensic knowledge that's price- body decays, enzymes convict the relative of the murders. less to law enforcement personnel across the in the digestive system country and around the world. begin to digest the tis- sues surrounding it The Chemistry of causing them to liquefy, Decomposition The Impetus called putrefaction. At The creation of a facility to chronicle the process the same time, insects A body releases about 450 known chemicals dur- of decomposition was spurred by a misidentifi- are attracted to the ing decomposition and researchers at the facility cation made by its founder Dr. Bill Bass in 1977. body and begin their are using an electronic nose with multiple sen- An experienced anthropologist, Dr. Bass was digital images at timed intervals, and making roles in reducing it to skeletal remains. As the sors to sample the air above and around a called upon to identify a body believed to be that meticulous notes. This careful study has revealed time span between death and discovery widens, decomposing body to gather more clues to of a Civil War colonel killed in battle and buried in much of what happens at every stage of decom- forensic techniques become less accurate as establish a time of death. a sealed lead coffin. While examining the body, position and is an invaluable tool for law enforce- environmental variables begin to affect the Decomposing bodies also leak fatty acids onto Dr. Bass observed a bit of pinkish flesh still ment officials to use when evaluating crime decomposition rate of the body and each envi- the surface where it rests. The profiles of these attached to the bones. Based on his experience scenes. ronment has a different effect. For example, in acids changes as the days pass and analyzing and the forensic knowledge available at the time, the summer heat, a body can be reduced to The facility typically houses over 20 corpses in them can reveal the time of death. It can also he concluded that the body had only been bones in just two weeks. Bodies inside cars various stages of decomposition and in various give clues as to how long the body has been in a interred for about a year. In reality, additional non- decompose at a faster rate because it is much environmental conditions. Bodies are buried in particular spot and if it may have been moved forensic clues proved that the body was that of hotter inside a car and the heat accelerates the deep and shallow graves, submerged in water, after death. the colonel and that Bass's estimate of the time rate of decay. Bodies submerged in water, left out in the open in both shade and full sun, of death was about 112 years off! This made Dr. wrapped in plastic, or located where the tempera- covered with tarps, wrapped in plastic bags, To achieve this, perforated pipes are situated Bass realize just how little was known about the ture is under 50° decompose slower for various rolled inside carpets, or placed in one of the old above and below the bodies and emissions are process of decomposition and motivated him to reasons. These variables and their effects are the cars on the lot so that scientists and students can collected with sorbent traps. The chemicals are gear his research toward expanding current sci- mysteries that Dr. Bass and his colleagues are observe how decomposition rates are affected by extracted and analyzed by gas chromatography entific knowledge about the decomposition of trying to unravel. conditions based in part on FBI files of past and mass spectrometry to be identified and quan- bodies. crimes and the body disposal methods used in tified. Then they are mapped along with the envi- those crimes. Insects Are The Key ronmental factors present during their collection The Facility to allow scientists to construct a timeline to deter- Most of the bodies have been donated to the In the first two weeks after death, insects are one mine time of death. It was 1977 and the original site the university facility for its research and some are unidentified of the best indicators scientists have to determine allowed the department to use was an old pig bodies turned over by the medical examiner's when death occurred. Different insects will be Future Hopes farm about twenty miles away from the campus. office. As the awareness of the facility has spread interested in a body at different stages of decom- After security became a problem at that location, and more people will their bodies to the facility, position. By studying the different insect life As work at the facility continues and bright young the university granted the department ownership the University lawyers have had to draft a special cycles present on a cadaver, scientists can deter- graduate students continue to filter through the of an empty lot behind the medical center that form for people to fill out for this purpose. mine how long the insect has been there. Cross- program, new technologies are an inevitable had previously been used to burn the hospital's referencing that information with known life result. Scientists theorize that the research being trash. Dr. Bass jumped at the chance to have the A true pioneer in his field, Dr. Bass has created a cycles and feeding habits of the particular insect done at the Facility may be used in the future to facility located closer to the university campus unique "school" for scientists and law enforce- can estimate a fairly accurate time of death. develop sprays to train cadaver dogs or hand- and in 1980 he and his students built a storage ment authorities alike. Of the 61 specialists certi- The cadaver-insect symbiosis can also be a clue held monitors that can detect the smells of shed, had the area fenced off, and the Body fied nationwide by the American Board of when two different rates of decomposition are decomposition at crime scenes. As the mysteries Farm was born. Forensic Anthropology, Dr. Bass trained one-third. observed, such as when a body is decomposing of death are unraveled and a detailed analysis of decomposition continues to be formulated, these In this unique outdoor laboratory, researchers and Agents from local and state law enforcement in a house or car and it has taken the flies and new technologies will make it easier for law graduate students study the process of decompo- departments and the FBI send field teams of other insects a while to find a way in. Careful enforcement to identify victims, find the perpetra- sition and how various environmental conditions agents to the facility to participate in courses that examination will show that the body's natural tors and ensure that these most heinous of affect the rate and stages observed. Scientists allow them to experience first-hand how crime decomposition advanced before the insects crimes will not go unpunished. learn from watching bodies decompose, taking scenes might appear. Facility workers prepare began their work. bodies to simulate crime scenes and the agents 2 Fisher Science Education Headline Discoveries Volume II, Issue I, Spring 2005 NEW! 7-12 CATALOG: PROFILE: Have you seen our new Fisher Science Education 2005/06 Catalog? DMITRI IVANOVICH MENDELEYEV If not, you're missing out on 1,500 1834–1907 new products.