9 Facts About Human Decomposition

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From rotting corpses crawling with maggots to oozing bodies emitting stomach-churning stenches, the decaying human body is the stuff of nightmares, horror movies, and crime dramas. We're both fascinated and repelled by decomposition, which has given rise to many myths and urban legends. (No, hair and nails don't grow after death, and corpses never sit up on mortuary tables.) Here are nine fascinating facts that demystify how we transition from flesh to bone to dust.

1. DECOMPOSITION STARTS ALMOST IMMEDIATELY AFTER DEATH.

It takes approximately four minutes from the moment a person has breathed their last for the shortage of oxygen in their body to kick off a series of events happening at the microscopic level: The levels of carbon dioxide and acidity rise in the bloodstream, and toxic wastes build up, poisoning the cells. Then, enzymes within cells begin to eat away at them. Organs with high concentrations of enzymes and water, such as the liver and the brain, are ground zero for this process.

One of the first visible signs of death is when the eyes cloud over, a result of fluids and oxygen no longer flowing to the corneas. That can begin within 10 minutes [PDF] of death.

2. THERE ARE FIVE PHASES OF DECOMPOSITION.

The first phase is called fresh. It's characterized by cell autolysis, "or self-digestion": The cells burst open due to the work of enzymes, and fluids leak out. Fluid-filled blisters emerge on the skin, which slips easily off the body in large sheets.

Meanwhile, resident anaerobic bacteria in the gut begin to break down cells, beginning the second phase of decomposition: bloat. As these microbes work away, gases begin to accumulate in the intestines, and the surrounding tissues expand. The gases react with hemoglobin, a protein found in red blood cells, producing a green pigment in the veins ("marbling"), and the skin turns green, then black.

During active decomposition, the third phase, tissues begin to liquefy and decomposition fluids seep out through orifices. According to Dawnie Wolfe Steadman, director of the Forensic Anthropology Center at the University of Tennessee, Knoxville, the loss of tissue mass is the chiefly the work of fly maggots—which feast on tissues—and bacteria.

Advanced decomposition is when most soft tissues are gone, whatever skin is left has turned dry and leathery, and the skeleton is visible, thanks to the handiwork of yet more bugs. "While the fly maggots no longer have much to feed on, other insects such as beetles come," Steadman says. "They are capable of breaking down the tougher soft tissues, like tendons, ligaments, and even cartilage."

Skeletal decay is the end of the decomposition process. A variety of factors result in the breakdown or fragmentation of bones. Acidic soil, for example, dissolves an inorganic mineral compound called hydroxylapatite—a mix of calcium and phosphate—that accounts for 70 percent of our bone material [PDF]. Bones can also disintegrate when they are subjected to a variety of physical forces, including being gnawed on by scavengers or being slowly eroded by the flow of water.

How long each of the above stages lasts depends on factors such as temperature, burial conditions, and the presence of microbes, insects, and scavengers. Active decomposition in particular is greatly influenced by the temperature; flies lay their eggs in warmer months, so decomposition tends to be slower in colder temperatures. Bones generally begin to bleach within the first year, and algae and moss may grow on their surface. Large cracks tend to form after about a decade.

3. RIGOR MORTIS IS ONLY TEMPORARY.

Fans of shows like Law & Order: SVU are likely to be familiar with rigor mortis, or the stiffening of the body’s muscles following death. It begins within two to six hours, originating in the face and neck and spreading outwards toward the limbs. Rigor mortis is the result of the two types of fibers in our muscle cells—actin and myosin—becoming tightly linked by chemical bonds that develop in response to lower pH levels in the cells, creating inflexibility [PDF]. But this rigidity goes away within 1 to 3.5 days, as the bonds between the muscle fibers break and the muscles relax, once again starting with the face. As this happens, the body can release feces and urine.

Rigor mortis occurs more quickly and persists longer in cooler temperatures than in warmer ones; according to one study, rigor lasted for 10 days in corpses refrigerated at 39°F in a mortuary. What happens right before death can influence rigor mortis too: A high fever will shorten how long it lasts, while vigorous physical activity will cause it to set in sooner. These effects are likely caused by a drop in the levels of the chemical ATP (adenosine triphosphate), an energy driver in cells, and increased amounts of lactic acid, which lower the pH in muscle cells.

4. DECOMPOSITION DOESN'T SMELL AS BAD AS YOU'D EXPECT.

“People think bodies always smell awful,” says Melissa Connor, director of the Forensic Investigation Research Station at Colorado Mesa University. “But while there are a few times and phases [where the] remains are odiferous, for the most part, the smell is not overpowering.”

Malodorous gases build through the bloat phase, but the smells lessen as decomposition progresses. According to Connor, in the summer, a corpse can pass through the odiferous stages in 10 days or less.

A mix of gases is responsible for the “sickly sweet” stench of death. Of these, putrescine and cadaverine—produced when bacteria break down the amino acids ornithine and lysine, respectively—emit distinctive noxious odors. These gases can be absorbed through the skin and compete with or displace oxygen—a potential health risk for people working with decomposing bodies in closed environments, such as underneath a house or in a well shaft. A recent study suggests that putrescine may act as a warning signal that death is near, triggering a “flight-or-fight” response.

5. DECOMPOSITION CAN SOMETIMES CREATE "SOAPY" CORPSES.

Another stinky by-product of decomposition is a waxy substance called adipocere. It's formed from fat under wet conditions through a process called saponification (the same basic chemical reaction by which soaps are made from fats). Fresh adipocere smells like ammonia, but over time, adipocere dries out and the odor disappears. Philadelphia’s Mütter Museum has a specimen of a corpse encased in adipocere known as the Soap Lady, who was exhumed in 1875 from a city cemetery. The Smithsonian has a male counterpart: Soapman, who was also found in Philadelphia in 1875 during the construction of a train depot. He died around 1800.

6. THE 'NECROBIOME' COULD HELP US DETERMINE TIME OF DEATH MORE ACCURATELY.

Forensic entomologists use insects to infer time of death, but there are other potential biological clues. According to Steadman, forensic scientists are researching how different species of bacteria can influence decomposition, and if bacteria can help identify individuals.

"Some researchers are looking at the necrobiome—or all the little bacteria and fungi that inhabit a corpse—and seeing if changes in the necrobiome can inform time of death," Connor says. By knowing which strains of bacteria and other microbes are present at each phase of decomposition, scientists can put together a microbial clock to help estimate the time since death. Some of these microbes come from our own microbiome; others come from the surrounding soil, or are carried to the body by flies, other insects, and scavengers.

7. WITHOUT BUGS OR BACTERIA, DECOMPOSITION CAN SLOW WAY, WAY DOWN …

In December 1977, in Franklin, Tennessee, the Williamson County Sheriff was called to an antebellum estate called Two Rivers. The owners had reported a disturbance in the small graveyard attached to the estate. There, the sheriff’s department found a headless male corpse dressed in formal wear atop the broken coffin of a Confederate lieutenant colonel named William Shy, who had died in 1864. Forensic anthropologist William Bass was asked to examine the body.

In his book Death’s Acre, Bass writes that the corpse had been preserved in the early stages of decomposition; the "flesh was still pink," he notes. He estimated the man had been dead a year at most. But some things didn't add up, which puzzled Bass. The style of clothing was dated and the shoes were made of old materials. The corpse’s head was later found in the coffin, and the teeth had not seen modern dentistry. All of this led Bass to suspect that the body was in fact Shy’s.

Turns out he was right the second time around. Shy's corpse had been unceremoniously yanked out of his resting place by grave robbers. The 113-year-old body was so well-preserved because it was embalmed—which slows decomposition (by how much depends on the embalming process)—and because the cast-iron coffin was hermetically sealed, keeping out any insects and microbes that would have pushed decomposition beyond the early stages.

More recently, in May 2016, an airtight metal casket was unearthed in a backyard in San Francisco. The home had been built on the site of a cemetery. Inside the casket was the well-preserved body of a toddler, Edith Cook, who had died in 1876. News reports don’t explicitly state whether Edith was embalmed, but old ads from the casket’s manufacturers boast that it offered “perfect protection from water and vermin.”

Still, cast-iron coffins aren't decomposition-proof: In other cases, they've exploded due to bloat-stage gases. This gas buildup has been a problem for some modern "protective" or "sealer" caskets too.

8. … AND ENVIRONMENTAL CONDITIONS CAN ALTER DECOMPOSITION.

Certain environmental conditions are ideal for preserving bodies and creating natural mummies—which are unique because the skin survives active decomposition.

A combination of low oxygen, highly acidic water, and cool temperatures in European peat bogs turns corpses into bog bodies. While the acidic water breaks down bones, tannins in the peat and the lack of oxygen preserve skin—every expression, wrinkle, and fingerprint—with astonishing detail. Famous examples include the Tollund Man and Lindow Man.

La Doncella, or “The Maiden,” is an ancient Inca teenager who was left to die in the Andes Mountains in Argentina as a part of a ritual sacrifice. She was found in 1999, head down, appearing to be asleep. Though she died more than 500 years ago, her hair, skin, and clothing are all almost perfectly preserved. The high altitude, low temperatures, and low oxygen level account for La Doncella’s condition.

Another example of the preservative powers of the mountains is Ötzi, a natural mummy of a man who died about 5300 years ago. He was discovered in 1991 in Ötztal Valley Alps and has been preserved almost in his entirety. Though the glacier ice dehydrated his body, his skin, other tissues, organs and bones remain in great shape.

9. DISEASES THAT KILL THEIR HUMAN HOSTS CAN SURVIVE DECOMPOSITION.

A number of disease-causing viruses can hang around even after death. The Ebola virus is particularly contagious even after a person has died: It remains in their blood and other bodily fluids. Any contact with broken skin or the mucous membrane (which lines the nose, mouth, and other body cavities) of a healthy person is enough to pass on the infection. For this reason, the World Health Organization recommends that infected bodies be buried quickly and safely, with everyone handling the body wearing protective gear and the body buried in a coffin in the ground. The virus has been shown to persist in dead primates for up to a week.

Norovirus (the stomach flu) can also spread in a manner similar to Ebola, and it is possible to catch influenza from the infected mucus of a dead person. The smallpox virus remains in the scabs of a dead person for as long as a century—but at least it's not contagious from the dead to living.

Looking to Downsize? You Can Buy a 5-Room DIY Cabin on Amazon for Less Than $33,000

Five rooms of one's own.
Five rooms of one's own.
Allwood/Amazon

If you’ve already mastered DIY houses for birds and dogs, maybe it’s time you built one for yourself.

As Simplemost reports, there are a number of house kits that you can order on Amazon, and the Allwood Avalon Cabin Kit is one of the quaintest—and, at $32,990, most affordable—options. The 540-square-foot structure has enough space for a kitchen, a bathroom, a bedroom, and a sitting room—and there’s an additional 218-square-foot loft with the potential to be the coziest reading nook of all time.

You can opt for three larger rooms if you're willing to skip the kitchen and bathroom.Allwood/Amazon

The construction process might not be a great idea for someone who’s never picked up a hammer, but you don’t need an architectural degree to tackle it. Step-by-step instructions and all materials are included, so it’s a little like a high-level IKEA project. According to the Amazon listing, it takes two adults about a week to complete. Since the Nordic wood walls are reinforced with steel rods, the house can withstand winds up to 120 mph, and you can pay an extra $1000 to upgrade from double-glass windows and doors to triple-glass for added fortification.

Sadly, the cool ceiling lamp is not included.Allwood/Amazon

Though everything you need for the shell of the house comes in the kit, you will need to purchase whatever goes inside it: toilet, shower, sink, stove, insulation, and all other furnishings. You can also customize the blueprint to fit your own plans for the space; maybe, for example, you’re going to use the house as a small event venue, and you’d rather have two or three large, airy rooms and no kitchen or bedroom.

Intrigued? Find out more here.

[h/t Simplemost]

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10 Facts About Real Genius On Its 35th Anniversary

Val Kilmer stars in Martha Coolidge's Real Genius (1985).
Val Kilmer stars in Martha Coolidge's Real Genius (1985).
Sony Pictures Home Entertainment

In an era where nerd is a nickname given by and to people who have pretty much any passing interest in popular culture, it’s hard to imagine the way old-school nerds—people with serious and socially-debilitating obsessions—were once ostracized. Computers, progressive rock, and role-playing games (among a handful of other 1970s- early '80s developments) created a path from which far too many of the lonely, awkward, and conventionally undateable would never return. But in the 1980s, movies transformed these oddballs into underdogs and antiheroes, pitting them against attractive, moneyed, successful adversaries for the fate of handsome boys and pretty girls, cushy jobs, and first-place trophies.

The 1985 film Real Genius ranked first among equals from that decade for its stellar cast, sensitive direction, and genuine nerd bona fides. Perhaps fittingly, it sometimes feels overshadowed, and even forgotten, next to broader, bawdier (and certainly now, more problematic) films from the era like Revenge of the Nerds and Weird Science. But director Martha Coolidge delivered a classic slobs-versus-snobs adventure that manages to view the academically gifted and socially maladjusted with a greater degree of understanding and compassion while still delivering plenty of good-natured humor.

As the movie commemorates its 35th anniversary, we're looking back at the little details and painstaking efforts that make it such an enduring portrait not just of ‘80s comedy, but of nerdom itself.

1. Producer Brian Grazer wanted Valley Girl director Martha Coolidge to direct Real Genius. She wasn’t sure she wanted to.

Following the commercial success of 1984’s Revenge of the Nerds, there was an influx of bawdy scripts that played upon the same idea, and Real Genius was one of them. In 2011, Coolidge told Kickin’ It Old School that the original script for Real Genius "had a lot of penis and scatological jokes," and she wasn't interested in directing a raunchy Nerds knock-off. So producer Brian Grazer enlisted PJ Torokvei (SCTV) and writing partners Babaloo Mandel and Lowell Ganz (Splash, City Slickers) to refine the original screenplay, and then gave Coolidge herself an opportunity to polish it before production started. “Brian's original goal, and mine, was to make a film that focused on nerds as heroes," Coolidge said. "It was ahead of its time."

2. Martha Coolidge’s priority was getting the science in Real Genius right—or at least as right as possible.

In the film, ambitious professor Jerry Hathaway (William Atherton) recruits high-achieving students at the fictional Pacific Technical University (inspired by Caltech) to design and build a laser capable of hitting a human-sized target from space. Coolidge researched the subject thoroughly, working with academic, scientific, and military technicians to ensure that as many of the script and story's elements were correct. Moreover, she ensured that the dialogue would hold up to some scrutiny, even if building a laser of the film’s dimensions wasn’t realistic (and still isn’t today).

3. One element of Real Genius that Martha Coolidge didn’t base on real events turned out to be truer than expected.

From the beginning, the idea that students were actively being exploited by their teacher to develop government technology was always fictional. But Coolidge learned that art and life share more in common than she knew at the time. “I have had so many letters since I made Real Genius from people who said, 'Yes, I was involved in a program and I didn’t realize I was developing weapons,'" she told Uproxx in 2015. “So it was a good guess and turned out to be quite accurate.”

4. Val Kilmer walked into his Real Genius audition already in character—and it nearly cost him the role.

After playing the lead in Top Secret!, Val Kilmer was firmly on Hollywood’s radar. But when he met Grazer at his audition for Real Genius, Kilmer decided to have some fun at the expense of the guy who would decide whether or not he’d get the part. "The character wasn't polite," Kilmer recalled to Entertainment Weekly in 1995. "So when I shook Grazer's hand and he said, 'Hi, I'm the producer,' I said, 'I'm sorry. You look like you're 12 years old. I like to work with men.'"

5. The filmmakers briefly considered using an actual “real genius” to star in Real Genius.

Among the performers considered to play Mitch, the wunderkind student who sets the movie’s story in motion, was a true genius who graduated college at 14 and was starting law school. Late in the casting process, they found their Mitch in Gabriel Jarrett, who becomes the third generation of overachievers (after Kilmer’s Chris and Jon Gries’s Lazlo Hollyfeld) whose talent Hathaway uses to further his own professional goals.

6. Real Genius's female lead inadvertently created a legacy for her character that would continue in animated form.

Michelle Meyrink, Gabriel Jarret, Val Kilmer, and Mark Kamiyama in Real Genius (1985).Sony Pictures Home Entertainment

Michelle Meyrink was a staple of a number of ‘80s comedies, including Revenge of the Nerds. Playing Jordan in Real Genius, she claims to “never sleep” and offers a delightful portrait of high-functioning attention-deficit disorder with a chipper, erratic personality. Disney’s Chip 'n Dale: Rescue Rangers co-creator Tad Stones has confirmed that her character went on to inspire the character of Gadget Hackwrench.

7. A Real Genius subplot, where a computer programmer is gaming a Frito-Lay contest, was based on real events.

In the film, Jon Gries (Napoleon Dynamite) plays Lazlo Hollyfeld, a reclusive genius from before Chris and Mitch’s time who lives in a bunker beneath their dorm creating entries to a contest with no restrictions where he eventually wins more than 30 percent of the prizes. In 1969, students from Caltech tried a similar tactic with Frito-Lay to game the odds. But in 1975, three computer programmers used an IBM to generate 1.2 million entries in a contest for McDonald’s, where they received 20 percent of the prizes (and a lot of complaints from customers) for their effort.

8. One of Real Genius's cast members went on to write another tribute to nerds a decade later.

Dean Devlin, who co-wrote Stargate and Independence Day with Roland Emmerich, plays Milton, another student at Pacific Tech who experiences a memorable meltdown in the rush up to finals.

9. The popcorn gag that ends Real Genius isn’t really possible, but they used real popcorn to simulate it.

At the end of the film, Chris and Mitch build a giant Jiffy Pop pack that the laser unleashes after they redirect its targeting system. The resulting popcorn fills Professor Hathaway’s house as an act of revenge. MythBusters took pains to recreate this gag in a number of ways, but quickly discovered that it wouldn’t work; even at scale, the popcorn just burns in the heat of a laser.

To pull off the scene in the film, Coolidge said that the production had people popping corn for six weeks of filming in order to get enough for the finale. After that, they had to build a house that they could manipulate with hydraulics so that the popcorn would “explode” out of every doorway and window.

10. Real Genius was the first movie to be promoted on the internet.

A week before Real Genius opened, promoters set up a press conference at a computer store in Westwood, California. Coolidge and members of the cast appeared to field questions from press from across the country—connected via CompuServe. Though the experience was evidently marred by technical problems (this was the mid-1980s, after all), the event marked the debut of what became the online roundtable junket.