The fascinating process of human decomposition

Last month I visited a body farm in Texas. So these are places where researchers take

recently deceased human bodies and they essentially just leave them out to decompose. So this

research, mainly it's helpful when law enforcement come across a body under mysterious circumstances,

maybe a murder, and they want to know how long has it been out here. The bodies are

scattered all over the field. They have about 50 out and most of them are under these metal

cages that prevent the vultures from getting in. I kept asking him to lift up the cages

for me to get better photos. So what happens right after you die is all the fluids that

are inside your cells when you're alive leak out and bacteria start feeding immediately.

There converting the liquids and solids inside you into gasses that they emit, and this causes

the second stage, which is bloat. You also have something called marbling during this

stage because one of the gases, sulfur, binds to the hemoglobin molecules in your blood

and changes the color of them to an orange or yellow. And at the same time, flies come.

They come almost immediately when the body is placed, and they lay eggs. And they especially

lay them in any orifices, so your head will get a lot of maggots on it -- the eye sockets

and mouth and nose, and they'll eat away at that first. They're absolutely just crawling

all over the body, like, getting up really close to it and taking photos was the most

intense thing I did there. Then after a few days of that, the body moves to the third

stage, which is called purge. And that's ultimately the bloating is relieved as a lot of the gas

and fluids leak out and you see this dark fluid pooling around the body. And the interesting

thing is that fluid is really nutrient rich, but it's so rich in nitrogen that it kills

off the plants initially. But a year later, it'll become especially fertile. So here this

is the next stage. A lot of the changes happen really rapidly at first, and then it slows

down a lot. There's certainly still bacteria here, but if you were to graph all the nutrients,

it's a very sharp decline. If the body is in the sun, especially in Texas, the heat

is so strong that a lot of bacteria and insects can't actually survive. And so instead of

continuing to decompose the body, it will really gradually mummify -- it'll just dry

up. But if the body is in the shade, then the bacteria and insects can continue to feed

on it and they'll essentially eat it down to a skeleton. With the vultures, the process

is completely different because a flock of them will just swarm a body immediately if

it's left uncaged, and they can eat pretty much all of the flesh off within a few hours.

One of the things that really fascinated me is the way that the bones are frayed. And

that's from their beaks ripping at it voraciously. And that looks like leather or clothing, but

it's skin. Typically they're left out to decompose for 6 to 12 months. So when the bodies come

in, they'll boil them and they put detergent on them and that strips away most of the remaining

flesh. And then volunteer undergraduate interns will clean every single bone with a toothbrush.

The smell was actually the strongest inside that lab. It smells like rotting meat, which

is essentially what it is -- you know, just organic substances that have gone bad. And

then after they get clean they get laid back out, they get labeled, and then they get sent

to the lab closer into town where they get boxed up. And so this basically serves as

a contemporary skeleton collection, which there aren't that many of, as it turns out.

We really seldom see bodies anymore in our modern culture. Most people die in a hospital.

They get directly sent to a funeral home. That funeral home injects them with formaldehyde

and puts makeup all over them, so they don't look like a dead body. But the truth is that

ultimately, whether we see it or not, this happens. Unless you get cremated, it's going

to happen to you. I mean, that's what ecosystems evolved to do -- is harvest nutrients

to create new life.