Everyone that you will be dissecting willfully donated their bodies when they were alive or their families donated after they pass away.

This is an anatomy class at Georgetown University School of Medicine.

It's not a morbid curiosity to learn of what was inside of us or to work with a dead person.

A professor is briefing a classroom full of anxious students in blue scrubs.

They are about to embark on a rite of passage, their first dissection of a human cadaver.

If you hit that perfect layer, then it just pulls right back.

See, yeah, there's kind of that little bit of white there, that connective tissue.

We learn about how human bodies work by studying dead ones.

And not just in the classroom. Researchers use

cadavers to study chronic illnesses. Medical device makers use them to test out new tools. The military

blows them up to measure its explosives. Science, education, and technology all rely on a steady stream of cadavers.

And a lucrative for-profit industry has arisen to fill the demand.

Last year alone, we placed more than 45,000 anatomical specimens for research, training, and education in 50 countries worldwide.

For the Freakonomics Radio Network, this is the Economics of Everyday Things. I'm Zachary Crockett.

Today, part one of a special two-part story,

cadavers. To understand how cadavers became a commodity, you have to go back a few hundred years

to a time when the study of anatomy was still considered a taboo.

In Western history, modern anatomy really begins in the 14th century.

It is the first time that humans have access to other humans to dissect.

That's Susan Lawrence.

She's a professor and head of the history department at the University of Tennessee, Knoxville.

She studies the history of cadavers.

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