45
BUTCHERING A DEER WITH OBSIDIAN TOOLS
Thomas R. Hester, Lee Spencer, Colin Busby and James Bard
47
During a seminar in experimental archaeology at the University of California,
Berkeley, in Fall, 1972, several class members designed an experiment involving the
use of obsidian flake tools in the skinning and butchering of a deer carcass. There
have been several other experiments involving the use of stone tools to skin and dis-
member animal carcasses. For example, there is the illustrated experimental use of
Paleolithic cleavers to butcher an African antelope (Howell 1970: 121), similar exper-
iments by L. S. B. Leakey (cf. Pfeiffer 1972: 403), Don Crabtree's notes on the use
of obsidian blades to skin a bear (Crabtree 1968: 470; Pfeiffer 1972: 402-403) and J.
Swauger's deer-skinning experiment utilizing Egyptian Paleolithic tools (Swauger and
Wallace 1964).
In preparation for the experiment, the seminar group viewed a film which
documented the use of chert flakes and bifaces in the skinning and butchering of a deer.1
Plans were also made to obtain the necessary obsidian raw material, to secure the deer
carcass, and to develop a system of recording the experiment.
'A deer carcass was obtained via a donation from the office of the Pleasanton,
California, Animal Control Unit (California Department of Fish and Game). The
deer had been illegally killed and had been confiscated by these authorities. The
specimen, a young doe, weighed 18.45 kg.
The lithic raw materials were obtained from the Glass Mountain obsidian
source north of St. Helena, California. L. Spencer then manufactured a series of
obsidian flake tools. These included naturally-backed flakes, large cortex flakes, blades,
and bifaces. As we assumed that most of these tools might be employed during the
course of the experiment, all were measured, their working edges examined under a
microscope, a description was written of each, and all were photographed.2
After the animal carcass had been obtained, and on the day preceding the
experiment, Spencer gutted the animal using several thick, naturally-backed obsidian
flakes. During the gutting process, the sternum and pelvis were broken with the use
of an obsidian chopper. Spencer, who had performed such tasks before using steel
hunting knives, was able to accomplish the gutting procedure in 40 minutes using the
obsidian tools. The gutted specimen weighed 10 kg.
On November 22, 1972, the seminar group performed the skinning and
butchering activities. The principal work was performed by Spencer since, as
mentioned above, he had substantial prior experience in animal butchering. Other
members of the seminar group assisted in the experiment by taking notes on the
sequence of activities, recording the tool used in each activity, and keeping careful
track of the amount of time each tool was used.
The obsidian tools used during the experiment (Fig. 1, a-e) were: #2: a
large naturally-backed flake; #4: a blade-like cortex flake; #7: an interior flake; #5:
a biface; and #10: a naturally-backed flake.
48
For the purpose of illustrating the detail in which the experiment was recorded,
we have provided below an edited version of the notes taken as the skinning and butcher-
ing sequence progressed:
TIME TOOL #
OBSEIR VATIONS
1:21
(pm)
10
1:24          " 'Y
1:25          i i
1:26
1:27
1 31
1:32
1:34
1:35
.. ?t
?. ..
it i?
i? .t
,t it
....t
1:36              1? it
1:38
1:40
1:41
1:42
1:44
1:45
1:46
1:48
1:50
1:51
1:52
1:53
..
II
.I
..
it
tI
it it
1t it
I.t I
It
II
II
It
II
Butchering commenced on one hind leg, cutting through hide on
underside taking care not to cut muscle, but rather only the
white membrane which attaches the hide to the muscle.
Pulls hide as he cuts this membrane.
Pulls skin loose and away from lower leg using tool in what can
be described as a delicate stroke or motion.
Skin free from leg and hip and ham area.
Starts a similar process on the other leg.
Cuts hide where attached to hoof area.
Cuts area around tail, frees hide, then pulls hide over back
without the aid of the tool.
With tool again, with much use of both hands, the hide is pulled
over the ribs.
Pulls hide above ribs toward front legs; minor edge wear
detected, described as small nicks.
Now cutting hide around the neck area. Hide is now off breast
area.
Hide is pulled over front leg, away from center of carcass.
Cut and pull hide away from leg.
Incision of hide around fore quarter; lateral or longitudinal cut
made along leg to facilitate hide removal.
Pulls hide off leg, final cuts to free the hide. Hide now pulled
towards body of deer.
Cuts hide around neck area.
Hide now free from body except around head area and right
front leg.
Still only minimal wear noted on the tool.
Lateral incision along leg.
Hide pulled from leg, now attached only to the head.
Pulls hide over head.
Cuts attaching muscle.
Chops off head, using a short chopping motion. There is use-
flaking present already. Now uses a slicing motion. Finish
use of tool #2. Head off after 1. 5 minutes.
Cuts around legs and back, separation of hind quarters from
spine, slicing and twisting of meat. (Holding meat, twisting
it in various directions as he slices).
Hind quarters separated.
..
I.
..
.I
It
2
[BREAK]
1:56      10
1:58    " "
TIME TOOL #
OBSER VATIONS
2:00    10
2:01
2
2:02    10
2:03
2:04
2:05
2:06
2:07
[B R
2:09
2:09.5
2:10
2:11
2:13
2:14
2:15
2:15.5
2:16
2:16.5
2:17
2:19
2:20
2:21
2:24
2:26
2:28
2:29
2:31
It it
Uses his foot to hold thorax and pulls fore leg away and cuts
with tool.
Uses tool 2 to slice off one fore quarter (this takes 10
seconds) and resumes use of tool 10.
Cuts off (small slabs) meat from thorax and works on other
fore quarter.
More use-flaking noted on tool 10, small nibbling along edge,
one or two small flakes detached.
(Another slab of meat removed from fore quarter shoulder)
Start slicing neck. Tool makes contact with bone.
Chop with tool 2 in order to remove neck from body. Slices
with same tool. Neck twisted as it is chopped.
Neck free from body.
it it
I I..
2
?I ft
IEAK]
5
2
5
5
2
5
2
5
it it
It ?t
it ??
4
it It
It it
....?
I? ..
2:34               it it
Tool 5 cuts very well.
0. 5 minutes with 2; hit vertebra.
Removes back-strap. Though the tool is now dull on the
sinuous edge, it nonetheless made a good tool for a sawing
motion. Back-strap removed.
Cuts back-strap into sections.
Separation of spine from hind quarters. Downward chop and
stroke used.
Twist hind quarters; hind quarters are separated.
Cutting back leg at hock, severed fendon, and switched to
tool 5 in process.
Started to separate lower leg at ankle.
Ankle and hoof are separate, cut behind hoof to sever tendon.
Tendon pulled out of leg.
Sinew removed with tool 5. Boning of thigh, separate knee
from thigh with tool 5.
Sawing motion.
Broke tibia from thigh area.
Boning of thigh or ham.
Begins use of tool 4. As boning continues, tool 4 occasionally
hits femur.
Remove skin from tendon.
Twist off hoof and lower leg area (hind quarter).
Circumscribe foreleg (hind above hoof) using blade to cut
through hide circumference. Experimentor uses his feet as
a brace.
Makes longitudinal cut on lower leg to remove tendon. Still
removing sinew from lower leg area.
Proceeds to bone-out other ham.
49
TIME~~~~~~ TOL      OBE AIN
2:35     2          Chops and cuts.
2:36     4          Work continuing.
2:37    "           Twist off tibia-fibula from thigh or ham.
2:40    "i"lFemur out of ham.
2:42    " "         Tool 4 seems dull after boning 1 1/2 hams.
2:43     5          Fleshing out neck, hitting vertebrae.
2:50    "i"lNeck sinew very fibrous.
2:52     7          On neck, removing sinews.
2:54                On fore leg, removes shoulder muscle.
2:55    " "1On other fore leg, hits bone occasionally.
3:00   tY?          Skinning-butchering completed.
3:01     2          Chop bone, a leg joint.
Tool #             Total time used (in minutes)
10                          38
2                          10.5
5                          22
4                          16
7                           8
Table 1. Time, in minutes, each obsidian tool was used during experiment.
In general, the skinning and butchering of the deer carcass was accomplished
with considerable efficiency using the obsidian tools. Irn most of the cutting movements,
the obsidian implement was drawn toward the experimentor; the next two most common
motions or movements involved sawing and pushing the tool away from the operator.
One particularly interesting observation was that the obsidian tools tended to "resharpen"
themselves during use. Due to the brittle nature of the tool edges, tiny flakes would
be detached during sawing or light chopping rasks. Spencer observed that most of this
spalling occurred when the tool came into recurring contact with bone and skin. 3 It
should be pointed out that while several tools were employed during the experiment, a
single obsidian flake implement (such as tool #10) could have been used to carry out the
entire skinning and butchering operation.
TIME TOOL#
OBSEIRVATIONS
51
Use-Wear Observations
As noted earlier, each tool had been checked prior to use, and the condition
of the intended working edge had been carefully recorded. After experimental use,
each tool was wrapped and labeled, and was later examined, with the use of a 75X
binocular microscope, for wear patterns resulting from the experiment. These data
are summarized briefly:
Tool #2. Prior to use, this tool (Fig. 1, a) had a very sharp edge, marred
only by two small nicks resulting from its detachment. The edge angle was 450*
During the experiment, the tool was used for 10. 5 minutes, and was involved in cutting
of the deer's neck (using a short chopping motion, coupled with a slicing motion), and
was also used to cut and chop at leg joints (see narrative above).
Extensive modification of the tool edge occurred during use. There is
continuous bifacial use--retouch. On the dorsal surface, there is use-retouch, with
flakes up to 15 mm. in length, although most are . 5 to 3 mm. in length. Accompanying
the use-retouch is nibbling and snapping of the edge. On the ventral face, there is
continuous use-retouch, with several major arc-shaped flake scars, 3 to 20 mm. long.
In addition to these alterations, crushing is noted along the cutting edge.
Tool #4. This blade-like cortex flake (Fig. 1, b) had a very sharp, unmarred
edge (angle, 320) prior to use. It was used for 16 minutes, primarily in cutting flesh,
although the cutting of hide was also done. The only visible wear after use is a
roughening or nicking of the edge, and a few small (. 05 to .1 mm. long) use-retouch
scars scattered along the edge.
Tool #5. This tool, an ovate biface (Fig. 1, c), had one edge thinned for
use (edge angle, 450). It was utilized for a total of 22 minutes, and was used primarily
for cutting along the vertebral column of the deer, and in removing the back-strap.
Later, it was used in the boning-out of the thigh, removal of sinew, and the
fleshing out of the neck, where it came into repeated contact with vertebra. Before use,
it had a sharp sinuous edge (without any marginal trimming). While it was being used
in the various activities described above, the experimentor observed that it was
beginning to feel "dull", though it was still serviceable for "sawing" activities.
Microscopic examination of the used tool edge revealed light crushing of the edge,
accompanied by scattered bifacial nibbling and use-retouch flakes. Given the comments
of the experimentor while using this tool, we had expected much heavier wear than
was observed.
Tool #7.  There was a very sharp umnodified edge (angle, 200) on this
naturally-backed flake (Fig. 1, d) prior to use. It was used for eight minutes near the
conclusion of the experiment, to remove sinews from the neck, and to remove muscles
on both forelegs; during the latter task, it occasionally struck the bone. As a result of
this use, the dorsal edge of the flake showed more or less continuous use retouch, with
52
the largest of the scars ca. . 5 mm long, but most in the range of .1 to .2 mm. On the
ventral edge, a few similar use-retouch scars were found, and near mid-edge, there was
a group of three striations, disposed perpendicular to the edge. These may have
resulted from contact of the tool edge with bone.
Tool #10. This tool (Fig. 1, e) was used for 38 minutes and was employed
extensively in the cutting of hide and flesh (see narrati've). The experimentor observed
that the tool, a naturally backed flake with a cutting edge angle of 300, could have
probably been used without modification to carry out the entire operation. Before use,
the tool had an unmarred, straight and sharp cutting edge. Although used for over
a half-hour, only minor edge wear was subsequently observed. This wear consisted
of a roughening or nicking of the edge ( i. e., several indentations in a previously
straight edge), and the removal of three use-retouch flakes, 1 to 3 mm. in length.
Concluding Remarks
The limited nature of an experiment such as the one reported here precludes
broad conclusions or far-reaching inferences. However, it does allow us to offer a
few comments on the use of obsidian tools in deer-butchering. Since obsidian was a
raw material widely used in central and northern California for the production of
utilitarian implements, we believe that some of the observations recorded during the
experiment will be of direct interest to archaeologists working in these regions.
Obsidian, with its extremely sharp edges, works very well in cutting, slicing,
sawing, and related tasks in deer butchering. Despite the brittle nature of the
material, use-wear is not easily incurred if the tool is used in the cutting or slicing of
hide and flesh. Pronounced wear will occur whenever the tool comes into repeated
contact with bone, as in the case of tool #2 used in severing the deer's neck, striking
the vertebral column on a number of occasions. Although one sharp-edged tool (#10)
was used for over 30 minutes in cutting tasks, only very minor wear resulted and the
tool was still serviceable at the conclusion of the experiment. One interesting techno-
logical factor that we observed was that the obsidian flake tools tended to "resharpen??
themselves; tiny use-retouch flakes and bits of the tool edge were continually being
removed during certain cutting or sawing activities, thus creating a new, sharp edge.
It should be emphasized that no intentional resharpening of tool edges was required
during the experiment.
Flake tools seemed to work much better in the butchering activity than did
the single biface (tool #5) that we tried. Shafer (1971: 103) notes similar results from
the comparative use of chert bifaces and flake tools in deer-butchering. The flakes,
in that experiment, functioned much more efficiently than the biface (of a form, as was
our obsidian biface, that archaeologists often call "knives"). The five chert flakes
used to skin and partially butcher the deer showed nicked edges and only faint dulling
appeared on the edges of two of the specimens.
53
In our experiment, the most useful of the flake tools proved to be those with
a flat or cortex-covered edge opposite the cutting edge (e.g., a naturally backed flake
like tool #10). All of the flake tools we used had acute edge angles (200-320).
Although we used a chopper (tool #2) in processing the deer carcass, the
entire task could have been accomplished just as easily without it (cf. Shafer 1971: 103).
And, as we noted above, the biface was of little value. Thus, a very simple, non-
specialized tool kit of obsidian flakes would be, upon analysis, the most efficient imple-
ments for the gutting, skinning, and butchering of a deer. 4 Such a possibility should
serve as a warning to those archaeologists who make subjective judgements about tool
functions (e.g., biface = "knife") and to those who continue to ignore flake assemblages
as a source of information of prehistoric activities.
54
NOTES
1        The film viewed by the seminar group rqcorded an experiment performed at
the Texas Archeological Research Laboratory. J. E. Corbin carried out the skinning
and partial butchering of a young deer, using five chert flakes to accomplish the entire
task. See Shafer (1971: 103) for a further discussion of this experiment. The film is
in the possession of R. L. Alexander, Dept. of Anthropology, University of Delaware.
2        An extensive series of Kodachrome slides were taken by seminar members
A. Albee and C. Busby.
3        The spalling of tiny flakes from an obsidian tool during meat-cutting activities
may help to explain the presence of such materials in prehistoric coprolites analyzed
from California (Nissen 1973: 69) and Utah (Fry 1970: 239).
4        A further experiment conducted by J. Bard, C. Busby and L. Spencer with a
similar sized deer utilizing a hafted biface and a tool kit of unmodified obsidian flakes
accomplished the butchering of the animal in approximately 30 minutes. In this
experiment the antler-hafted biface was discarded after a short period of use (2-3
minutes) because it became too slippery to hold during the butchering activities. The
rest of the butchering was conducted using four unmodified flakes and a large angular
obsidian chunk ("chopper") and was completed using the same sequence of steps out-
lined in the present report.
55
BIBLIOGRAPHY
Crabtree, D.E.
1968
Fry, G. F.
1970
Howell, F. C.
1970
Nissen, K.
1973
Pfeiffer, J.
1972
Shafer, H.J.
1971
Mesoamerican Polyhedral Cores and Prismatic Blades. American
Antiquity 33(4): 446-478.
Preliminary Analysis of the Hogup Cave Coprolites. Appendix III
in: Hogup Cave (C. M. Alkens), University of Utah Anthropological
Papers 93.
Early Man. Time-Life Books, New York.
Analysis of Human Coprolites from Bamert Cave, Amador County,
California. In: The Archaeology of Bamert Cave (Ama-3),
Amador County, California (R. F. Heizer and T.R. Hester): 65-
71. Archaeological Research Facility, Berkeley.
The Emergence of Man. 2nd. ed. Harper and Row, New York.
Investigations into South Plains Prehistory. Papers of the Texas
Archeological Salvage Project 20.
Swauger, J. and B. L. Wallace
1964     An Experiment in Skinning With Egyptian Paleolithic and Neolithic
Stone Implements. Pannsylvania Archaeologist 34: 1-7.
b
C
0  f           r        ~~~~~~0?
cm
e
d
Figure 1. Obsidian Tools Used in Deer-Butchering Experiment. a Tool #2; b, Tool
#4; c, Tool #5; d, Tool #7; e, Tool #10. Transverse cross sections are shown for
a and c. Horizontal lines along the tool edges indicate those areas of the tool used
during the experiment. All tools retaining the bulb of percussion and striking platform
(a, b, d, e) are oriented with the bulb and platform down (i. e., toward the bottom of the
page).