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Experimental replication shows knives manufactured from frozen human feces do not work



The ethnographic account of an Inuit man manufacturing a knife from his own frozen feces to butcher and disarticulate a dog has permeated both the academic literature and popular culture. To evaluate the validity of this claim, we tested the basis of that account via experimental archaeology. Our experiments assessed the functionality of knives made from human feces in controlled conditions that provided optimal conditions for success. However, they were not functional. While much research has shown foragers to be technologically resourceful, innovative, and savvy, we suggest that this ethnographic account should no longer be used to support that narrative.
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Journal of Archaeological Science: Reports
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Experimental replication shows knives manufactured from frozen human
feces do not work
Metin I. Eren
, Michelle R. Bebber
, James D. Norris
, Alyssa Perrone
, Ashley Rutkoski
Michael Wilson
, Mary Ann Raghanti
Department of Anthropology, Kent State University, Kent, OH 44242, USA
Department of Archaeology, Cleveland Museum of Natural History, Cleveland, OH 44106, USA
The ethnographic account of an Inuit man manufacturing a knife from his own frozen feces to butcher and disarticulate a dog has permeated both the academic
literature and popular culture. To evaluate the validity of this claim, we tested the basis of that account via experimental archaeology. Our experiments assessed the
functionality of knives made from human feces in controlled conditions that provided optimal conditions for success. However, they were not functional. While much
research has shown foragers to be technologically resourceful, innovative, and savvy, we suggest that this ethnographic account should no longer be used to support
that narrative.
1. Introduction
In his book, Shadows in the Sun,Davis (1998: 20) recounts what is
now arguably one of the most popular ethnographic accounts of all
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, de-
fecated, 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.
Since publication, this story has been told and re-told in doc-
umentaries, books, and across internet websites and message boards
(Davis, 2007, 2010;Gregg et al., 2000;Kokoris, 2012;Taete, 2015).
Davis states that the original source of the tale was Olayuk Narqitarvik
(Davis, 2003, 2009). It was allegedly Olayuk's grandfather in the 1950s
who refused to go to the settlements and thus fashioned a knife from his
own feces to facilitate his escape by skinning and disarticulating a dog.
Davis has admitted that the story could be apocryphal, and that in-
itially he thought the Inuit who told him this story was pulling his leg
(Davis, 2009: 207, 2014: 15). Yet, as support for the credibility of the
story, Davis cites the auto-biographical account of Peter Freuchen, the
Danish arctic explorer (Hodge and Davis, 2012). Freuchen (1953) de-
scribes how he dug himself a pit to sleep in and woke up trapped by
snow. Every eort to get out that he tried failed. Finally, he recalled
seeing dog's excrement frozen solid as a rock. So, Freuchen defecated in
his hand, shaped it into a chisel, and waited for it to freeze solid. He
then used the implement to free himself from the snow: I moved my
bowels and from the excrement I managed to fashion a chisel-like in-
strument which I left to freezeAt last I decided to try my chisel and it
worked(Freuchen, 1953: 179).
While tools manufactured from human feces are not unprecedented
in the human technological record (Chen et al., 2018;Mayor, 2009;
Persson and Hågeru, 2018;Tran-Thi et al., 2017), we do not believe
that Freuchen's account can serve as support for the Inuit account for
two reasons. First, while we do not have any reason to suspect that
Freuchen was prevaricating, to our knowledge there is no veriable
evidence beyond Freuchen himself that this event occurred. Second, a
chisel is a very dierent tool than a knife. The mechanics of use are
distinct, and the worked substrates in the Inuit and Freuchen cases are
dierent. The Inuit case features the cutting and slicing motions on
tissue, muscle, and tendon; the Freuchen case presents the pounding
and chipping of snow.
Given the current ambiguity surrounding Davis' (1998) account of
an Inuit using his own frozen feces as a knife, we conducted an ex-
periment to test whether such a knife can function. Rather than conduct
an actualisticbutchery experiment, we designed a more controlled
test that involved the simple slicing of materials necessary to skin and
disarticulate dog: hide, muscle, and tendons. We reasoned that if knives
manufactured from human feces cannot cut hide, muscle, and tendons
in a simple, controlled setting, then the notion that such knives could be
Received 12 August 2019; Received in revised form 22 August 2019; Accepted 3 September 2019
Corresponding author at: Department of Anthropology, Kent State University, Kent, OH 44242, USA.
E-mail address: (M.I. Eren).
Journal of Archaeological Science: Reports 27 (2019) 102002
Available online 10 September 2019
2352-409X/ © 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license
used to butcher an entire animal would also not be supported. However,
if such knives could cut through these materials, then future tests could
systematically increase the complexity of the experiments for additional
support (Mesoudi, 2011).
2. Materials and methods
In order to procure the necessary raw materials for knife production,
one of us (M.I.E.) went on a diet with high protein and fatty acids,
which is consistent with an arctic diet, for eight days (Binford, 2012;
Fumagalli et al., 2015) (Table S1). The Inuit do not only eat meat from
maritime and terrestrial animals (Arendt, 2010;Zutter, 2009), and
there were three instances during the eight-day diet that M.I.E. ate fruit,
vegetables, or carbohydrates (Table S1).
Raw material collection did not begin until day four, and then
proceeded regularly for the next ve days (Table S1). Fecal samples
were formed into knives using ceramic molds, knife molds(Figs.
S1S2), or molded by hand, hand-shaped knives(Fig. S3). All fecal
samples were stored at 20 °C until the experiments began.
We procured pig hide, muscle, and tendons, and these were also
stored at 20 °C until two days before the experiments began, at which
point we allowed them to begin thawing at 4 °C. Minutes prior to the
experiment, both the knife moldsamples and the hand-shaped
kniveswere removed from the laboratory freezer and further shar-
pened with a metal le (Fig. S4). The knives were then buried for
several minutes in 50 °C dry ice to ensure they were suciently
frozen before any attempt at slicing. The study was approved by the
Institutional Biosafety Committee at Kent State University.
3. Results
We began our cutting experiments with the hide, reasoning that if
our knives could not cut hide, then subsequent attempts with muscle
and tendons would be futile.
Neither the knife moldsamples, nor the hand-shaped knives
could cut through hide (Figs. S5S6). Despite the hide being cold from
refrigeration, instead of slicing through it the knife-edge simply melted
upon contact, leaving streaks of fecal matter (Fig. S4).
We repeated the experiment using the fecal samples of another team
member (M.R.B.), whose diet was more traditionally Western (see
supplementary online materials). The hand-shaped kniveswere sub-
ject to the same procedures and temperatures as the rst set of knives
(Figs. S7S8). However, these knives also did not cut through the hide.
For curiosity's sake, we tried to cut the subcutaneous fat on the un-
derside of the hide. With some diculty, only the shallowest of slices
could be produced, and the knife-edge still quickly melted and dete-
riorated (Fig. S9).
4. Discussion
Countless ethnographic, archaeological, and experimental observa-
tions robustly support the narrative that indigenous and prehistoric
people are technologically resourceful, innovative, and savvy (Derex
et al., 2019;Oswalt, 1976;Thomas et al., 2017;Williams et al., 2019). It
is thus unsurprising that an ethnographic account consistent with this
narrative an Inuit person extemporaneously fashioning a knife out of
his own frozen feces to survive the arctic night has been so widely and
positively transmitted. Our experiments, however, tested the techno-
logical basis necessary to support that account, and our results suggest
that knives manufactured from frozen human feces are not functional.
Our results should be considered in light of our use of 50 °C tem-
peratures; a metal le to sharpen the blades; and a cold, hairless hide
rather than a warm, hair covered hide, the latter representative of a
fresh kill. In other words, we gave our knives the best possible chance to
succeed and they still could not function.
While future experiments may introduce the prospect of dierent
diets, it is unlikely that this would have a signicant impact. Our
butchery occurred in a room with a temperature of approximately
10 °C, and thus future experiments might examine colder contexts. We
suspect this will also fail to yield dierent results than those presented
here, as the time between the removal of a blade from the dry ice and
the slicing of meat was instantaneous. The use of saliva to sharpen a
frozen fecal blade, as the original account describes (Davis, 1998),
might also be examined. However, based on the work of McCall and
Pelton (2010), we are skeptical that saliva will increase fecal blade
ecacy. They (McCall and Pelton, 2010: 103) recently examined the
possibility that, rather than aking and chipping stone into butchery
tools, humans in cold regions aked and chipped ice. While these re-
searchers' experiments demonstrated that ice could be fractured into
butchery tools somewhat analogous in form to those made from stone,
the actual use of such ice tools was ineective. Their ice knives quickly
melted when in contact with heat sources such as their hands, despite
the use of gloves. Analogous to our fecal knives, the sharp ice edge also
melted in contact with the various objects they tried to cut. Their results
preclude the use of ice in environments near or above freezing, cutting
objects above freezing, or the tool being used by a human.
Societal narratives and policies are often constructed from anthro-
pological and scientic claims (Grayson and Meltzer, 2003). While the
narrative that indigenous and prehistoric people are technologically
resourceful and innovative is widely supported, these narratives suer
when an untested claim is used to support it. If one untested claim is
used to support a stance even if that stance is otherwise supported,
ethical, or just then there is no logical reason why a second untested
claim cannot then be invoked. The use of untested claims then becomes
the norm, and can be used to support stances that are benecial to
society, as well as those that are harmful. 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
Data and materials availability
All data is available in the main text or the supplementary materials.
We would like to thank Andy Howard, Chris Hunt, Clive Bonsall,
Peter Rowley-Conwy, and an anonymous reviewer for their comments
on an earlier version of this manuscript. We would also like to thank the
positive and constructive feedback from countless archaeologists who
heard this paper presented at the 2019 Society for American
Archaeology conference in Albuquerque, New Mexico.
Author contributions
Conceptualization: MIE; Investigation: All authors; Methodology:
MIE, MRB, MR; Resources: MIE, MRB, MR; Writing: All authors.
Declaration of competing interest
Authors declare no competing interests
Appendix A. Supplementary data
Supplementary data to this article can be found online at https://
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