This comes from a story Wade Davis told about an old Inuit hunter guy who killed a dog with a poop knife, skinned it, made a sled from its carcass and a harness from its hide and used another dog to ride into the sunset as a fuck you to his family who were trying to force him to retire.
The story has been thought to be bullshit by a lot of people. Wade Davis is a great writer though.
In 1983, Davis first advanced his hypothesis that tetrodotoxin (TTX) poisoning could explain the existence of Haitian zombies.[10] This idea has been controversial and his 1985 follow-up book (The Serpent and the Rainbow) elaborating upon this claim has been criticized as containing scientific inaccuracies.[11] One is the suggestion Haitian witchdoctors can keep "zombies" in a state of pharmacologically induced trance for many years.[12] As part of his Haitian investigations, Davis commissioned the exhumation of a recently buried child.[13][14] (Dead human tissue is supposed to be a part of the "zombie powder" used by witchdoctors to produce zombies.) This has been criticized as a breach of ethics.[12][15]
I remember the 2018 Society for American Archaeology conference, everyone saw this paper title in the schedule and tried to go to the talk. Probably the most asked question that weekend besides "time for a beer?" was "did you see the poop knife talk?"
The paper's introduction actually does explain it:
In his book, Shadows in the Sun, Davis (1998: 20) recounts what is now arguably one of the most popular ethnographic accounts of all time: “There is a well known account of an old Inuit man who refused to move into a settlement. Over the objections of his family, he made plans to stay on the ice. To stop him, they took away all of his tools. So in the midst of a winter gale, he stepped out of their igloo, defecated, and honed the feces into a frozen blade, which he sharpened with a spray of saliva. With the knife he killed a dog. Using its rib cage as a sled and its hide to harness another dog, he disappeared into the darkness.”
There's also the story of Danish explorer Peter Freuchen, who claims to have used his own frozen shit to make a chisel to dig himself out of some ice. The paper takes the time to say that it is strictly about knives, though, not chisels
Did they experiment with composition of the poop? I expect it matters what you ate. I can see it not working if they were on a high fibre diet. They should try again after eating some sharp cheddar.