Decomposition
Research,  The life of a writer

How Could 1 Body Decompose at 3 Different Rates?

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DecompositionIn late November/early December, something on a Discovery ID show blew my mind. On the dramatization of this real case, the detectives investigated a dead body found in the Oregon forest. Nothing new there, right? Here’s the kicker … The victim was decomposing at three alarmingly different rates. The corpse was not dismembered, either. One intact body, from head to foot, but with three different decomposition processes taking place at the same time.

The legs looked fresh. No change in appearance, very little, if any, discoloration. The torso had decomposed enough to show most of the ribcage, with exposed, decaying organs. As if that wasn’t bizarre enough, only hair was left on the head, the scalp sliding off a bare skull. No face, no tissue, nothing left but bone and teeth.

This rarity baffled the forensic expert they called to the scene. It also drove me crazy, because they never said what caused it. Instead, the show concentrated on the multiple homicides and finding the suspect. Probably made for better TV. A short comment at the end of the show stated they hadn’t unraveled the mystery. At the time of the homicide, that may have been true, or they just didn’t want to shift focus.

Either way, “We don’t know” just wasn’t a good enough answer for this particular crime writer. The missing piece to this forensic mystery drove me crazy. Can you guess what I did next? Yep. I turned to my love of research. 🙂

A month later, and the forensic anomaly still haunted me. I needed to learn enough to quell my own curiosity, or I’d never be able to let the case rest. Inquiring minds want all the facts, not the Hollywood, edited version. So, I started my own investigation. Problem was, I couldn’t remember which show I saw this on (we watch a lot of true crime). Googling all variations of “How can a body decompose at three different rates?” led nowhere.

I rolled up my sleeves and dug in …

My Investigation

The dramatization showed the body lying with her upper-torso and head in the shade, legs in the sun. Which didn’t make any sense as far as decomposition goes. The forensic expert also didn’t mention any change in ambient temperature from head to foot. So, I wrote it off to Hollywood lighting, and moved on.

Environment has a lot to do with decomposition, so I figured the Oregon forest itself may hold some answers. On the show, these seasoned investigators were familiar with the area. They’d investigated hundreds of homicides. There had to be something more, something minute, maybe even something not visible to the naked eye.

We know decomposition follows four stages …

AUTOLYSIS: The first stage is called autolysis, or self-digestion, and begins immediately after death. As soon as blood circulation and respiration stop, the body has no way of gaining oxygen or removing wastes. Excess carbon dioxide causes an acidic environment, which also causes cell membranes to rupture. The membranes release enzymes that begin eating the cells from the inside out. Blood settles with gravity, creating lividity.

After several hours, rigor mortis stiffens the muscles. Small blisters filled with nutrient-rich fluid form on internal organs and the skin’s surface. The body looks to have a sheen due to ruptured blisters. The skin’s top layer loosens. Anaerobic organisms in the digestive tract will multiply, producing acids and gases.

BLOAT: Leaked enzymes from autolysis produce numerous gases. The sulfur-containing compounds that the bacteria release also cause skin discoloration. Due to the gases, the human body can double in size. The microorganisms and bacteria produce extremely unpleasant odors called putrefaction. These odors can linger long after a body has been removed.

ACTIVE DECAY: Fluids released through orifices indicate the beginning of active decay. Organs, muscles, and skin become liquefied. When all of the body’s soft tissue decomposes, hair, bones, cartilage, and other byproducts of decay remain. When the cadaver purges, it loses most of its fluids and mass (tissue). Insects and animals also scavenge the body. Where the body lay, soil staining occurs and may temporarily kill some of the surrounding vegetation. Years later, that same vegetation will grow thicker and fuller due to the added nutrients.

DRY/SKELETAL REMAINS: The timing of this stage varies by environment. If there’s any skin left, it will be leather-like and tough. Basically, the body is reduced to bones and connective tissue. Some beetles and insects may colonize a body for shelter or feeding on other insects and connective tissue. Over time the bones may bleach (turn white) with exposure to sunlight.

Forensic Taphonomy

Forensic taphonomy is the use of processes associated with decomposition in the investigation of crime. These processes can estimate post-mortem interval, as well as post-burial interval, and loate clandestine graves. In recent years, significant advances give scientists a better understanding of decomposition and its affect on gravesoil. Meaning, the soil underneath the corpse. Recent research shows that a cadaver can have a significant affect on the biology and chemistry of associated soils and these effects can change as decomposition proceeds.

Ah, now we’re getting somewhere. What if differing pH levels in the soil played a role in this case? Chemical changes in soil react to decomposing bodies. Specifically, pH levels and carbon dioxide.

Carbon Dioxide and pH Levels

I found a study where the scientist placed 1.5 grams of lamb muscle into pots of soil for six weeks. To see if soil type might affect the chemical signature of decay, he used soils that differed in pH. Each week, he measured the soils’ pH and the carbon dioxide levels.

After three weeks, he discovered that muscle tissue in acidic soil decomposed three times faster than in alkaline. The concentration of carbon dioxide emitted from the pots changed at the same rate as the muscle tissue decomposed. Meaning, three times heavier concentration in acidic soil.

He also detected pH changes. After seven days, the pH of acidic soil rose by over 3 units, but the alkaline soil pH only slightly increased. Decomposing bodies release ammonium ions, which raise the pH in the acidic soil, but don’t significantly affect soil that is already alkaline.

Then I found this …

In forest ecosystems, chemical breakdown of recalcitrant organic matter into simpler compounds is mediated largely by enzymes. Fungi release extracellular enzymes, which decompose forms of plant litter that contain high amounts of cellulose and lignin. These enzymes are also involved in decomposing soil organic matter.  Extracellular enzymes are classified by the mechanisms by which they break apart organic matter. Oxidative enzymes decompose complex substrates such as lignin, while hydrolytic enzymes are used to breakdown simpler compounds, such as carbohydrates.  

My Theory

What if the killer got lucky when he dumped that poor woman, and her body happened to land on three different soil types? The acidic soil under her head sped up decomposition, then the acid slowly declined further down the body. Under her legs, the soil was high in alkaline. And the torso lay on the perfect combination of both. Varying soil types attract different insects, which devour flesh at their own rate. Thus, speeding up or slowing down decomposition on the part of the body where they fed.

The body in question was found in the Oregon forest. If the forest ecosystem toys with the chemical breakdown of organic matter, then the location also seems to support my theory.

What do you think? Any other ideas on how this forensic mystery might occur?

 

Sue Coletta is an award-winning crime writer and an active member of Mystery Writers of America, Sisters in Crime, and International Thriller Writers. Feedspot and Expertido.org named her Murder Blog as “Best 100 Crime Blogs on the Net.” She also blogs on the Kill Zone (Writer's Digest "101 Best Websites for Writers"), Writers Helping Writers, and StoryEmpire. Sue lives with her husband in the Lakes Region of New Hampshire. Her backlist includes psychological thrillers, the Mayhem Series (books 1-3) and Grafton County Series, and true crime/narrative nonfiction. Now, she exclusively writes eco-thrillers, Mayhem Series (books 4-9 and continuing). Sue's appeared on the Emmy award-winning true crime series, Storm of Suspicion, and three episodes of A Time to Kill on Investigation Discovery. When she's not writing, she loves spending time with her murder of crows, who live free but come when called by name. And nature feeds her soul.

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30 Comments

  • Randy K Brown

    January 9, 2019 at 11:37 PM

    Sue, the amount of sunlight that part of the body received could be an added factor. Lotion applied to the legs–body lotion, insect repellent, and sun screen–could be a factor. And you’re right about soil acidity could vary under each part of the body. A decomposing plant, mushroom or other fungi, animal waste (different animals, herbivores, meat eaters and omnivores all leave different Ph levels in wastes)
    Some forests in Oregon are growing on top of volcano flows which could make a difference–lots of exposed cinders that break down and scatter in the wind
    You might try contacting Oregon State Police and/or the State medical examiner. If you decide to make a field trip, let me know. 🙂
    Randy K Brown recently posted…A Christmas story I recommend to everyone By Randy BrownMy Profile

    • Sue Coletta

      January 10, 2019 at 7:39 AM

      All excellent points, Randy. Volcanic ash, really? Wow. Who knew? I thought about contacting the police, but I figured they must get inundated with calls after one of these shows.

      I would love a research trip! Unfortunately, Oregon is very difficult to get to from NH. I wanted to go to conference there a couple years back. The travel time equaled a trip to Hawaii. For some reason, there’s no easy way to get there from here, without spending 10-12 hours traveling. Crazy, right?
      Sue Coletta recently posted…Canines for Conservation — Amazing Dogs!My Profile

  • Mae Clair

    January 8, 2019 at 10:38 AM

    How odd and bizarre. I have no clues or suggestions to offer, but I can see why it would have driven you crazy. I bet it’s something you could work into one of your books!

  • Madonna

    January 7, 2019 at 4:45 PM

    I would wonder if the killer hadn’t removed the facial skin/tissue speeding up the decomposition process of the head, the torso I expect would decompose more quickly due to the gut bacteria…. the legs in the sun maybe inhibited insect action?

    • Sue Coletta

      January 7, 2019 at 4:54 PM

      I wondered that, too, Madonna, but investigators said the killer didn’t remove the flesh off the face. Turns out, he was a rather stupid killer.

      Usually the sun speeds up decomposition. I wish they gave me more to go on, but the show wasn’t about the forensics, oddly enough. I would’ve loved a follow-up episode on this very subject. Alas, crime writers obviously aren’t their target audience. *sigh*

  • Garry Rodgers

    January 7, 2019 at 9:27 AM

    Funny you should write on this, Sue. I had a case very similar to this on Vancouver Island back in the 1990s while still a cop. The forest conditions on VI in British Columbia are similar to those in Oregon. What we had was a guy shot and dumped down a bank beside a road in a remote wooded area. He was there 13 days (we later established) and was discovered after his smell started wafting up to the roadway and someone going by on a bicycle sniffed him, looked over and then called it in. It was late June and the start of hot weather (85-90F).

    The body was in a contorted position -half prone/half supine, if you can visualize it – with legs upward, torso bent to expose the right back side and the face straight up with the hands exposed. He was dressed in only a pair of basketball-type shorts and unlaced, high-top runners – no shirt or anything else.

    His decomp was the weirdest thing ever. The pelvic area and upper thigh was a mix of clean and rot, the exposed lower legs were part bone and part stringy flesh, feet were pristine (being wrapped in the shoes), but his upper torso was a mix of advanced putrification/mummification/late rigor. His face was completely gone and the scalp had slipped. His finger tissue was mostly missing but his mid-arm area was still in reasonable shape.

    WTF? None of us had ever seen something like this including the seasoned coroner. We had a forensic pathologist at the scene as well as a forensic entomologist to deal with the bugs. To make a long story short, we had a combination of things happening. It wasn’t the soil acidity – it was the sun and the insects. The body lay in a site where it had limited but intense sunlight exposure at mid-afternoon when rays are strongest. As well, the sun only had brief exposure periods on the body as it passed overhead due to a maze of tree screenings. As well, the shorts and shoes somewhat insulated the flesh from sunlight and heat.

    The pathologist referred to it as a “Zebra” effect. Because there was an on-again/off-again solar intensity, different body areas decomposed and dehydrated at different rates. That, in turn, gave better feeding opportunities to insects who’d rather chew rotten flesh than still-good stuff. It was like a zipper or keyboard of decomp.

    Now, how he was killed was a whole different manner. It took us 2 months to ID him. There was only one partial fingerprint left that was too poor to search but it was an unusual pattern for the digit it was on. That gave us a shot at eliminating some subjects by their “ten-count”. DNA was too early for a bank back then. We had awesome dental charts but no name to link. Most of the tattoos were obliterated and the only other non-body thing we had was the clothing – which appeared brand new. We even took his skull to the bug tank and cleaned it up for reconstruction and an artist rendering (BTW, the sketch was bang-on when we later ID’d him).

    So who was he and who killed him? At the autopsy we found a .22 lead bullet in what was left of his viscera. Plus we had a nicked hyoid bone with lead traces. So we knew he was shot in the throat and somehow the bullet worked its way to the gut. How it happened, who he was and whodunnit was amazing -one in a million- and it’s the subject of “Beside The Road” which I’ll put out late this year. No spoiler alert – you’re gonna have to wait for it 🙂

    • Sue Coletta

      January 7, 2019 at 12:42 PM

      Wow, Garry. Your case sounds a lot like this one. ‘Course, forensic taphonomy as it relates to soil didn’t exist then, so are you sure the soil didn’t also play a role in your case?

      The victim here was barefoot, but otherwise fully clothed. They had an forensic artist do fascial reconstruction, too, in order to ID her. As you mentioned, dental records are no good without someone to match them to. Investigators speculated she was strangled, but only because that’s how he killed the other victims. I wish I knew the conditions of the sun vs. where the victim was found. Wouldn’t it be odd for the sun to completely miss both legs?

      The zebra effect intrigues me. Uh-oh, you’re gonna lead me down another research rabbit hole. 🙂
      Sue Coletta recently posted…How Could 1 Body Decompose at 3 Different Rates?My Profile

      • Garry Rodgers

        January 7, 2019 at 4:23 PM

        I don’t recall soil conditions ever being questioned but it’s a good point. From what I know, flesh breaks down faster in alkaline conditions as opposed to acidic, hence the old lye trick for getting rid of bodies, but I’m really not sure. And forensic taphonomy was new by the time I hit the coroner business, never mind back in the police days. So it is very possible that your theory holds water. I suspect the sun might have missed the legs because of the right size and placement of a tree that never allowed sunlight to directly hit that area. That’s what was going on in our case.

        Investigators always have to keep in mind that body condition is really only relevant to time of death. If that can be established by some independent means, then it doesn’t matter a hoot how ripe the vic was. Bit of a hint for “Beside The Road” – we had a physical date parameter at the scene because there was a McDonalds bag pinned by the corpse that had to be there when or before he was dumped. Our lab did an amazing job of reconstructing a drive-thru receipt even though it was contaminated with goo. Another TOD kicker – once we got a good lead on who the guy was and what went down, we linked him to a liquor store robbery on the night he was killed. We had clear video of the victim taken a couple hours before death, so we knew a precise time and date. What took us so long to get a name to the body was where the guy had been and what he’d been up to before arriving in town. None of us in the local police knew he existed so it was completely baffling… so was his mechanism of death 🙂
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  • C.S. Boyack

    January 7, 2019 at 9:12 AM

    But I can’t see it making that much difference if the body is on top of the soil in the open air. Buried in it, yes. What about some influence by predators. Coyotes have been known to eat until they puke. That would add acids right onto the corpse. )The tasty bits are in the middle. Even your beloved crows and ravens will start at the soft parts. It’s very curious.
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    • Sue Coletta

      January 7, 2019 at 8:48 AM

      Right? The show obviously wasn’t meant for writers, or they would’ve included more details about the forensics, rather than brushing over it and hoping we didn’t notice. I almost whipped the remote across the room when the show ended without any answers to this fascinating forensic mystery.

      Thanks, Staci. The soil is the only thing that makes sense to me. I’m surprised the internet didn’t blow up with searches after the show. Instead, *crickets*
      Sue Coletta recently posted…How Could 1 Body Decompose at 3 Different Rates?My Profile

  • Margot Kinberg

    January 7, 2019 at 7:28 AM

    That is a fascinating phenomenon, Sue! And I think you’ve got a very solid theory as to how it happened. I’m even wondering whether it wasn’t just a case of the killer getting lucky. Perhaps the killer knew something about the area and picked that place? I didn’t watch the show, so I don’t know the killer’s background, but I wonder whether that place might have been chosen deliberately.