No, knives made from frozen human feces do not work

That's not a knife... *this* is a knife.

Jackson Ryan Former Science Editor
Jackson Ryan was CNET's science editor, and a multiple award-winning one at that. Earlier, he'd been a scientist, but he realized he wasn't very happy sitting at a lab bench all day. Science writing, he realized, was the best job in the world -- it let him tell stories about space, the planet, climate change and the people working at the frontiers of human knowledge. He also owns a lot of ugly Christmas sweaters.
Jackson Ryan
3 min read

This knife is made from frozen human feces. It does not cut.

Eren et al/Journal of Archeological Science Reports

Making a knife out of frozen human feces is not an effective way to make a knife.

Until Thursday, I'd lived blissfully unaware of the Poop Knife. You probably had, too. But during the annual Ig Nobel prize ceremony, celebrating science that "makes you laugh, then makes you think," a research team from Kent State University and the Cleveland Museum of Natural History took out the prize in material science for making and testing knives made out of frozen human feces. The Poop Knife is real. 

Their study, published in the Journal of Archaeological Science: Reports in October 2019, details the process of freezing and molding a knife out of human excrement and testing its ability to cut through pig hide.

Wild. But, let's back up a little. 

First of all, why? The researchers point to the book "Shadows of the Sun," by anthropologist Wade Davis. The novel details the tribulations ("a well known account") of an old Inuit man who was to be forced from his home and moved to a settlement. He refused to leave and so his family took away his tools, presumably to get him to move. He apparently took to creating his own tools, by dropping his pants and defecating on the ice. He then "honed the feces into a frozen blade, which he sharpened with a spray of saliva."

But the scientists were skeptical. How much truth was there to this story?

To find out, the lead researcher ate an "arctic diet" high in protein and fatty acids for eight days, and began collecting his feces at day 4, for five days. The feces were then shaped into a knife by using molds or by hand-shaping the poop. You can see one of the hand-shaped knives at the top of the article. 

The team stored the knives at -58 degress Fahrenheit before trying to cut pig "hide, muscle, and tendons" which were thawed out. 

No poop knives were able to cut through the hide. There was some shallow slices on the hide underside and that was it. But even more impressive is the team used another researcher's fecal samples and tried again -- but this researcher's diet was "more traditionally Western." Same result. 

The team concluded "knives manufactured from frozen human feces are not functional." Hard to argue with that. They note they gave their knives the best possible chance to succeed and still failed to register a deep cut. They note the saliva used in the Inuit man's account is also not used in their study, but they are skeptical this would help. 

Ultimately, they say "Anthropologists must actively seek out unsupported claims, assumptions, rumors, and urban legends, and by testing them ensure any narratives that follow are as sturdy as possible" and untested claims can hurt the widely supported narrative that indigenous and prehistoric people are technologically resourceful and innovative.

Other IgNobel winners from Thursday included a study that examined eyebrows to identify narcissists and the management prize which went to five professional hitmen in China who were contracted for a hit job and then subcontracted it out for a fee ... without anyone actually performing the murder.

You can see the winners list here, but the poop knife takes out the coveted CNET IgNobel of the Year, which I just invented.