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tallying for taphonomy 271




figure 7.2. Relationship between years since death and the maximum weathering stage
displayed by bones of a carcass (r = 0.872, p < 0.0001). Plotted numbers indicate frequency of
carcasses displaying a particular weathering stage and years since death. Data from Behrens-
meyer (1978).


weathering stage displayed by the groundward surfaces. An example of such a graph
using ¬ctional data is shown in Figure 7.3. What is shown is what is expected in an
assemblage that experienced minimal post depositional disturbance “ the ground-
ward surfaces are generally less weathered than the skyward surfaces.
No taphonomist has used a quantitative unit for tallying weathering data other
than NISP. Some analysts, beginning with Behrensmeyer (1978), have suggested
that perhaps frequencies of weathered long bones should be tallied separately from
frequencies of small, compact bones, such as carpals, tarsals, and phalanges, and
perhaps as well scapula, innominates, skulls, and vertebrae should be tallied as a
group separate from long bones (one group) and small bones (another group). Do
femora weather at the same rate as phalanges? Actualistic data suggest that they do
not (summarized in Lyman and Fox 1989; see also Lyman 1994c). Thus, one might
tally the number of each skeletal element displaying each weathering stage. If com-
parison of the weathering pro¬les of, say, scapulae and humeri are not signi¬cantly
different, then lump them together for a skeletal composite weathering pro¬le. Mul-
tiple such comparisons between different categories of bone size and shape may
quantitative paleozoology
272




figure 7.3. Weathering pro¬les based on ¬ctional data for a collection of bones with
skyward surfaces representing one pro¬le and groundward surfaces representing another
pro¬le.


indicate that, say, small, more or less spherically shaped dense bones such as carpals,
tarsals, and phalanges, and larger, plate-shaped less dense bones, such as scapula and
innominates, may reveal differences in weathering pro¬les (for a discussion of how
to measure bone shape, see Darwent and Lyman [2002]). Similarly, one might sepa-
rately tally weathering stages evident on bones of large ungulates and those evident
on bones of small ungulates, or equids and bovids, or the like to evaluate similarities
or differences between taxa in terms of weathering.
Quanti¬cation of bone weathering data involves counting bones or counting kinds
of bones (skeletal element, or bone shape) based on the maximum weathering stage
displayed by each. The basic counting unit is NISP, but different kinds of NISP
(shape, size, taxon considered or not) may be distinguished. The entire specimen
(regardless of kind) is subject to weathering yet the longest exposed (if you will)
portion of the specimen will display the maximum degree of weathering. Recall why
the most advanced weathering staged displayed by a specimen is recorded rather
than a less advanced stage. The conceptual clarity of the relationship between the
target variable and the measured variable is what makes the quanti¬cation of bone
weathering attributes straightforward relative to some other kinds of taphonomic
tallying for taphonomy 273


attributes. The entire surface of each discrete specimen can potentially weather at the
same rate “ all surfaces are taphonomically interdependent at a general level because
they are all connected “ and although this does not seem to happen in practice
(groundward surfaces weather slower than skyward surfaces), interdependence of all
surface area of a specimen renders NISP the correct quantitative unit if one wishes
to know which of two assemblages of bones is the most weathered.
If post-depositional disturbance is of interest, then knowing the stage of weather-
ing displayed by skyward and by groundward surfaces is important. If intraskeletal
variation in weathering is of interest, then tally by distinct skeletal parts. If taxonomic
variation in weathering is of interest, then tally skeletal parts by taxon. The target
variable and how to tally should be speci¬ed by the research question. In most cases,
each specimen will be tallied based on the maximum weathering it displays. Weath-
ering stage data are generally tallied using NISP. One might tally weathering by NSP
to determine if a higher proportion of NUSP displays more advanced weathering
than NISP; if so, that would suggest long-term exposure on the ground surface and
a low NISP:NSP ratio that resulted from subaerial weathering. The interdependence
of the entire surface of a specimen dictates the tallying protocol, and it also attends
the tallying of other sorts of taphonomic modi¬cations to bones.



CH E M I C A L CO R RO S I O N A N D M E CH A N I C A L A B R A S I O N


Some faunal remains have passed through a digestive tract and as a result have
been chemically corroded (e.g., Andrews 1990). Corrosion features on bones include
solution pits or ovoid depressions, ¬ssures that penetrate through cortical bone, and
feathered fracture surfaces (Darwent and Lyman 2002; Klippel et al. 1987; Lyman
1994c). Quanti¬cation of such observations typically involves tallying the NISP that
display digestive (or other) corrosion and then calculating the percentage of the
total NISP that display corrosion (e.g., Fernandez-Jalvo and Andrews 1992; Klippel
et al. 1987; Weissbrod et al. 2005). (Seldom is the percentage of NSP that displays
digestive corrosion reported; it might be taphonomically revealing to compare the
percentage of NISP that has been digested with the percentage of NUSP that displays
digestive damage.) Because the entire specimen is ingested, all areas of the surface
of the specimen are interdependent with respect to the action of the taphonomic
process of digestive corrosion. NISP (or NSP) thus is the logical quantitative unit for
tallying digestive corrosion.
Given that stages of the degree of corrosion can be de¬ned (e.g., Darwent
and Lyman 2002; Fernandez-Jalvo and Andrews 1992; Matthews 2002), one might
quantitative paleozoology
274


construct a digestive corrosion pro¬le analogous to a weathering pro¬le (Figure 7.1 ).
The frequency data used to construct the pro¬le would allow graphical and statisti-
cal comparisons between assemblages of bones that may have undergone different
levels of digestive corrosion like those applied to weathering data. We do not yet
know enough about digestion and how, say, hair as in owl pellets might buffer some
portions of a bone specimen™s surface area from corrosion. Once we know this, some
research questions may demand that the range of the degree of corrosion damage to
a specimen be recorded.
What is often referred to as root etching is another kind of corrosive damage that is
sometimes reported. Again, taphonomic interdependence of all areas of the surface of
the specimen makes NISP the quantitative unit of choice. But, upward surfaces may
display root etching whereas downward surfaces of specimens do not (this seems to
be the case). If so, and as yet we seem to know too little about root etching to be sure,
then this sort of corrosive damage could be quanti¬ed by number of skyward surfaces
and number of groundward surfaces. Until we know more about the taphonomic
process itself, quantitative units have ambiguous signi¬cance; we do not presently
know what corrosion damage quanti¬ed using NISP means. Exactly the same can be
said for frictional abrasion such as occurs during ¬‚uvial transport and other sorts of
damage that have the potential to in¬‚uence the entire surface of a specimen. Until
we know better, NISP is the quantitative unit of choice for measuring corrosion and
abrasion.
But there may be a better quantitative unit for such features. One might measure the
amount (proportion) of surface area that displays corrosion, erosion, and abrasion
damage, although this would require a labor-intensive analysis. Whether one uses
NISP or the amount of surface area as the quantitative unit will depend on the target
variable. Often, what that target variable might be is unclear in the literature. If the
desire is to compare two assemblages, then it may make no difference whether percent
of surface area or percent of NISP that displays a kind of damage is determined. Until
we have better knowledge of the relationship between particular measured variables
and particular target variables, using NISP will suf¬ce. The same argument applies
with equal force to quantifying the taphonomic signature of the effect of ¬re on
faunal remains.



B U R N I N G A N D CH A R R I N G


Quanti¬cation of burned bone has, like other taphonomic features, typically involved
determination of the percentage of the total NISP that comprises burned specimens
tallying for taphonomy 275




figure 7.4. Frequency distribution of seven classes of burned bones in two kinds of
archaeological contexts. Original data from Cain (2005).


(e.g., Cain 2005; Edgar and Sciulli 2006; Grayson 1988; Pozorski 1979). One could also
tally the percentage of NSP that has been burned. Because burning is a process that
results in continuous modi¬cation of bone tissue “ burning is a result of excessive
heat “ different stages of burning can often be distinguished. One of the simplest
schemes to operationalize was speci¬ed by Brain (1981 :55) who designated three
stages: (1) unburned bone; (2) “carbonized” bone that is black because as the collagen
is burned a specimen becomes charcoal or carbonized; and (3) “calcined” bone that
is white because continued heating has oxidized the carbon. There is the potential
for even ¬ner distinctions of how intensively burned individual specimens are (e.g.,
Cain 2005; Johnson 1989; Shipman et al. 1984).
Tallying specimens by the maximum burning stage each displays, one can construct
a “burning pro¬le” much like a weathering pro¬le. Figure 7.4 shows the percentage
frequencies of bone specimens <2 cm long from the Middle Stone Age site of Sibudu
Cave, South Africa. Cain (2005) presented these data for six individual hearths and
two individual “ash complexes.” His data are summed by functional context (hearth
vs. ash complex) in Figure 7.4. That ¬gure suggests burning is similar across the two
kinds of contexts. Cain (2005) does not present his data in a manner that allows χ 2
analysis, analysis of adjusted residuals, or calculation of the evenness of representation
of burning stages such as was done with the weathering data in Figure 7.1 . These
sorts of quantitative analyses would be logical next steps.
quantitative paleozoology
276


It may be informative if bones are tallied in categories distinguished by burning
stage and also by taxon and skeletal element represented (or NISP and NUSP, given
that more specimens in the more advanced stages of burning in NUSP than in NISP
would suggest burning related fragmentation reduced the proportion of identi¬able
specimens). Thus, say, one could have burning pro¬les the tally categories of which
are identical to those described for weathering. And, like with weathering, record the
maximum burning stage represented over an area of at least 1 cm2 . In the absence
of insulating soft tissue, all areas of the surface of each specimen are taphonomically
interdependent and unless the specimen is quite large the entire specimen may well
undergo the same degree of heating. One could indicate on drawings of bones which
portions of each specimen are unburned, carbonized, and calcined, but without a very
speci¬c research question or hypothesis that demands such data (an explicit target
variable), and a solid (actualistically evaluated) interpretive model for making sense
of such data (mechanical linkages between burned and unburned portions of each
specimen and the heating regime), recording which surfaces are burned and which
are not, irrespective of the boundaries of the discrete specimen seems unnecessary.
One critical point concerns (in)explicit identi¬cation of the target variable. Is
it merely the proportion (or percent) of burned specimens? Is it the intensity of
burning? If intensity of burning is the target variable, then the manner in which
that variable is de¬ned by the analyst will specify the appropriate variable to mea-
sure. If intensity is de¬ned in terms of the amount of burned bone, then surface area
would be the appropriate measured variable. But if intensity is de¬ned in terms of
the number of burned specimens, then it would be better to use NSP (or NISP) to
quantify burning, and to determine the percent (or proportion) of specimens that
had been burned because that measured variable is the de¬nition of the target vari-
able. Whatever the case, the validity of all of the measured variables for assessing a
particular target variable is presently unclear because the nature of the relationship
between the two is unknown. Nevertheless, the discussion to this point warrants a
brief digression.



A Digression

All of the taphonomic processes that have been discussed thus far create modi¬cations
on the surface of a specimen, but all of them may, for myriad reasons, modify only
a fraction of the total surface area of a specimen. This fact can be taken advantage
of when tallying for taphonomy. If the portions of the total surface area of each
specimen are not interdependent with respect to the operation of a taphonomic
tallying for taphonomy 277


process or agent, then rather than tally the total NISP, the total NISP with the
modi¬cation of interest, and division of the latter by the former to derive a %NISP
with the modi¬cation, a different quantitative protocol can be applied “ this can be
referred to as the surface area solution.
The ARC GIS procedure described in Chapter 6 and ¬rst described by Marean et al.
(2001 ) might prove to be a good means for measuring the amount of total surface
area that displays maximum weathering, corrosion, burning, or other taphonomic
attributes. If this procedure is chosen, then the amount of surface area measured will
depend on how accurately specimens are “mapped” onto the computer-stored tem-
plates of skeletal elements, and also how accurately weathered, corroded, and burned
areas are mapped onto the templates. More importantly epistemologically, however,
is the fact that the taphonomic signi¬cance of measurements of amount of weath-
ered, corroded, and burned surface area is unclear. We do not know enough about
taphonomic processes to be able to interpret these surface area data with any validity.
The surface area solution is thus but one way to measure taphonomic attributes. It
may not be worth pursuing because taphonomic processes are so historically con-
tingent as to be beyond the analytical ¬ne-scale resolution provided by measures
of proportions of modi¬ed surface area (Lyman 1994c, 2004c). Description of other
means to quantify other sorts of taphonomic features will clarify this.



G N AW I N G D A M A G E


It has long been known that various animals gnaw bones for diverse reasons (Fisher
[1995] and references therein). Generally, damage created by rodent gnawing is readily
distinguished from gnawing damage created by carnivores (Fisher 1995; Noe-Nygaard
1989). Taphonomic knowledge is suf¬cient to allow the distinction of several kinds
of damage created by carnivores; these include punctures, furrows, and irregular
damage (e.g., Haynes 1980). The NISP (NSP, less often) of gnawed specimens is
usually tallied, and the relative (percentage) abundance of gnawed specimens [100 —
NISP gnawed/(NISP gnawed + NISP not gnawed)] determined for each taxon, for
each skeletal part or portion of a taxon, or however the analyst believes the data
should be structured (which will depend in part on the research question, which in
turn should explicate the target variable and the measured variable) (e.g., Todd et al.
1997). Thus, one could tally the frequency of femora that display punctures and the
frequency that display furrows, and compare those to the frequency of humeri that
display punctures and the frequency that display furrows, respectively. Or, determine
the relative frequency of gnawed femora and the relative frequency of gnawed humeri
quantitative paleozoology
278


to determine if femora were more extensively (or frequently) gnawed than humeri
(e.g., Cruz-Uribe and Klein 1994). The percentage of specimens of taxon A that have
been gnawed can also be compared with the percentage of specimens of taxon B that
have been gnawed (e.g., Cruz-Uribe and Klein 1994).
The frequency of gnawed specimens is often interpreted as a measure of the inten-
sity of gnawing. One might argue, however, that the number of gnawing marks per
gnawed specimen is a better measure of gnawing intensity and whether the remains
of one taxon or one kind of skeletal element has been more intensively gnawed than
the remains of another taxon or another kind of skeletal element, respectively. Such a
measure demands two things, one logical and one practical. The logical requirement
is that “intensity of gnawing” be clearly de¬ned. The practical requirement is that
individual gnawing marks “ ones made by each biting action or each instance of
dragging teeth across a bone surface “ be distinguishable from one another, but they
often are not. Perhaps, however, this is not really a problem. Is a gnawing mark a single
puncture, or furrow, or instance of irregular damage? Was each individual puncture
or furrow or instance of irregular damage created by one bite, or one instance of
teeth contacting bone or dragging across the surface of a specimen?
To answer the last two questions requires that we de¬ne intensity of gnawing. Most
taphonomists likely mean how damaged the specimens are or how much energy was
expended by the bone gnawer. More gnawing marks may well mean more energy was
expended, or it might not (Kent 1981 ). More gnawing marks may simply mean greater
damage to bone surfaces. This ambiguous target variable brings us back to how to
tally such damage, regardless of the meaning of that damage or its frequency. Let™s
assume we can distinguish individual gnawing marks. Whereas individual punctures
and furrows could each be tallied as “1,” the category known as irregular damage
presents a problem because individual tooth marks are typically indistinguishable
in such damage. (The lack of distinguishability is particularly acute with respect to
individual rodent gnawing marks [Thornton and Fee 2001 ].) But irregular damage
also suggests a different way to measure the intensity of gnawing damage.
One could determine the amount of surface area that has been destroyed by gnaw-
ing. Given that there is little clear taphonomic signi¬cance to the difference between
tooth punctures, furrows, and irregular damage, the amount of surface area that
has been destroyed by such modi¬cations may well provide a robust measure of the
intensity and degree and extent of gnawing damage. And, such a measure does not
demand that individual tooth marks be distinguished within an irregularly damaged
area. Rather, only the amount of the total surface area of all specimens could be
inspected for gnawing damage, and the amount (percentage) of surface area actually
damaged, regardless of the type of damage (punctures, furrows, irregular) could be
tallying for taphonomy 279


determined. One could determine such a value for both damage created by rodent
gnawing and damage created by carnivore gnawing, if desired. This brings us back
to the surface-area solution to tallying for taphonomy when burning, weathering,
and corrosion damage were under consideration. If that protocol is used, then the
problem reduces to accurate mapping of specimen borders and of boundaries of
damaged surfaces (see the discussion in Chapter 6).
Assuming that one can accurately determine the amount of damaged surface area,
other questions arise. Should the amount of corroded/abraded surface area be sub-
tracted from the total surface area inspected for gnawing damage? What about the
amount of weathered surface area? Answers to these sorts of taphonomic questions
need to be in hand before too much energy is spent designing new ways to quantify
traces of taphonomic processes and agents. Thus, for the present, the ratio of gnawed
specimens to gnawed plus ungnawed specimens, expressed as a percentage or propor-
tion, is an acceptable measure of gnawing intensity. There is a ¬nal, general category
of damage to bone surfaces that, at least from a zooarchaeological perspective, may
help bring the preceding portion of this chapter into ¬ne-resolution focus.



B U TCH E R I N G M A R K S


Butchering is the human reduction and modi¬cation of an animal carcass into usable
or consumable parts (Lyman 1987a, 1992b, 2005b). It involves the set of hominid
behaviors and activities that occur between the time of carcass procurement (regard-
less of how it is procured [e.g., hunted or scavenged] or its condition) and ¬nal dis-
posal or abandonment of variously consumed, and unconsumed, used and unused
portions of the carcass. Butchering behaviors occur in varying orders and frequencies
or intensities at various times for different carcasses because butchering is histori-
cally contingent, which means that the particular order and frequency of individual
behaviors depends on a plethora of variables such as carcass size, carcass location
on the landscape, time of day, air temperature, number of butchers, and butchering
tools available. Butchering activities have traditionally been categorized as belonging
to one of three or four basic kinds: skinning, dismemberment or disarticulation,
¬lleting or removing meat from bones, and marrow and grease extraction (Binford
1981 ; Guilday et al. 1962; Noe-Nygaard 1977; Pozorski 1979). The ¬rst two sets of
activities are focused on reducing a carcass into manageable pieces whereas the third
focuses on extraction of consumable meat external to the bones and the last set of
activities focuses on extraction of within-bone nutrients. There are a plethora of
other activities involved, including evisceration, extraction of blood, brains, bone,
quantitative paleozoology
280


and sinew, and periosteum removal that can take place but that can be subsumed
within one of the three or four traditionally recognized general activities.
Each butchering activity, regardless of how it is categorized, can produce what are
typically called butchering marks. Many believe that such marks can be reliably and
validly identi¬ed (e.g., Blumenschine et al. 1996; Fisher 1995), so here the focus is on
how these marks are quanti¬ed. The reasons to worry about counting butchering
marks are several. Most simply, butchering is a process; it begins with a single discrete
entity (carcass) and ends up with multiple discrete entities (disarticulated and dis-
associated complete and incomplete skeletal elements, hide, brain, marrow, muscle
masses, etc.). As butchering progresses, the carcass is reduced into successively more
numerous discrete pieces. The butchering process often involves the application of
various kinds of forces to the carcass to reduce it into consumable and usable pieces.
These forces can modify bones by breaking them and they can modify bone surfaces
by scarring them. It is the marks that are created by butchering that are of interest
here; quantitative measures of fragmentation are discussed in Chapter 6.
As the butchering process continues, more marks may be created on the bones of a
carcass. It is likely for this reason that many zooarchaeologists have sought to measure
the intensity of butchering, by which is meant, it seems, the amount of energy invested
in butchering. Butchering intensity is measured by tallying butchering damage evi-
dent on a collection of faunal remains (e.g., Haynes 2002). For example, Binford
(1988:127) suggested that “the number of cut marks, exclusive of dismemberment
marks, is a function of differential investment in meat or tissue removal.” Other
zooarchaeologists have tallied frequencies of various kinds of butchering marks for
other reasons. Bunn and Kroll (1986:432), for example, state that “frequencies of
cut marks on different skeletal parts can be directly linked to the skinning, disar-
ticulation, and de¬‚eshing of carcasses” and that multiple occurrences of marks in a
particular anatomical location indicate, say, “repeated dismemberment of the elbow
joint.” Regardless of the reason for tallying frequencies of butchering damage, if they
are to be tallied, we must ¬rst have explicit de¬nitions of what the various kinds of
damage are. It is to that topic that we turn next.



Types of Butchering Damage

There are several variables that may be considered when tallying butchering marks,
but one of them is virtually always considered. That variable concerns the type of
mark. There are several basic kinds of marks the morphologies of which are dependent
on the type of force and aspects of force application used to create them (Fisher 1995;
tallying for taphonomy 281


Green¬eld 1999; Lyman 1987a; Noe-Nygaard 1989; Potter 2005; Thompson 2005). It
is likely because of the different kinds of force and different ways that force is applied
through an intermediary (tool) to a bone surface that most zooarchaeologists can
reliably and validly distinguish the various mark types that have been recognized
(Blumenschine et al. 1996).
One kind of force involves dynamic percussion, such as when a hammer stone
impacts a bone resting on a ¬rm surface. This type of force application involves
a more or less blunt (as opposed to sharp-edged) implement and abrupt dynamic
loading (impact) that produces impact notches, ¬‚ake scars, and various scratches
(Blumenschine and Selvaggio 1988; Pickering and Egeland 2006). Another kind of
force involves sawing or slicing forces that produce what are termed “cut marks” or
“striae.” Sawing and slicing involves force application parallel to the long axis of the
cutting edge of the tool. Scraping is similar to slicing and sawing, though the latter
two are generally back and forth whereas the former is generally in one direction
and force is applied perpendicular to the long axis of the implement™s working edge.
Chopping is dynamic loading with a sharp edge; Gifford-Gonzalez (1989) considers
it to be a cutting-like process, and although it can be, I conceive of it as something
of a hybrid between cutting and percussion.
Percussion marks, cut marks, and scraping marks tend to have been produced in
prehistoric contexts by butchers with primitive (preindustrial) technologies. Chop-
ping marks are made in such contexts as well, but they are also made in historic
contexts by butchers with industrial-grade (metal) technologies (Landon 1996). So,

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