Zooarchaeological analysis, at its simplest,
consists of a tabulation of the taxons present in an assemblage. The presence/absence
of mammal, fish, bird, reptile, or amphibian remains in a faunal assemblage
is determined by the study of the morphology of each bone. Before species
identification can be undertaken, the skeletal element that a bone represents
must be determined. Element identification also allows estimation of age
at death and, in some cases, determination of sex to proceed.
Taxonomic Identification
Zoological classification follows the basic hierarchy: Kingdom, Phylum,
Class, Order, Family, Genus, and Species. Zooarchaeology deals exclusively
with the Kingdom of Animalia. Some zooarchaeology, including the study
of crustaceans, deals with Phylum other than Chordata but for the purposes
of this project, only the Chordata Phylum, animals with a spinal cord
or vertebral column, will be analyzed.
Class identification includes the sorting of a faunal assemblage into
mammal, fish, bird, reptile and amphibian remains and usually is undertaken
as the initial sort of an assemblage. The simplest method for determining
the Order of faunal remains is through analysis of teeth, which preserve
well in archaeological contexts. Common Orders encountered in zooarchaeology
include carnivores and primates. If teeth are unavailable for this determination
the functional morphology of each skeletal element is used for the identification
of Order, Family, Genus, and Species.
Element Identification
Within each taxonomic class, such as mammal, fish, or bird, the basic
shape and number of the elements of the skeleton are fairly constant.
Determining the Class of a bone therefore narrows the range of possibilities
of the element that it represents. Complete elements are, of course, the
easiest to identify but in many cases even small fragments of a bone contain
enough diagnostic morphology to allow for identification. It is therefore
important to document the completeness of an element to assess the certainty
of identification and to establish the number of each element that is
actually represented in an assemblage. For example, four femur fragments
do not necessarily equate to four femurs.
Age & Sex Determination
Many mammalian bones are made up of a central shaft, or diaphysis, which
is capped on each end by an epiphysis. The region between the diaphysis
and the epiphysis, the metaphysis, represents the region where bone growth
occurs. In juvenile mammals, the epiphysis is not fused to the shaft to
allow for this growth. The timing of the fusion of the epiphysis and shaft
occurs at different ages for each element. For example, the last element
to completely fuse in a human is the collar bone or clavicle which usually
occurs around the age of 40 years, well after the complete fusion of the
humerus which occurs at approximately 21 years of age. The patterns of
wear of teeth can also be used to estimate an animal's age. Malnutrition
can cause both of these methods to produce a high degree of error.
The ability to determine an animal's sex from skeletal elements varies
greatly with species and element. Some animal species demonstrate sexual
dimorphism, or size variation between the sexes, which assists in this
analysis. Antlers, dental variations, and pelvic apertures are other useful
means for identifying the sex of a skeleton or isolated skeletal element.
|
|
Common
Zooarchaeology Taxa |
|
Bear (grizzly) ……Ursus horribilis
Beaver………......Castor canandensis
Bear (American, black).Ursus americanus
Chipmunk (eastern).Tamias stiatus
Coyote…………..Canis latrans
Deer (mule) ……..Odocoileus hemionus
Deer (white-tailed).Odocoileus virginianus
Fox (gray) …Urocyon cinereoargenteus
Fox (red) ………..Vulpes vulpes
Hare (snowshoe)....Lepus americanus
Moose/Elk……….Alces alces
Opossum...............Didelphis marsupialis
Prairie Dog……....Cynomys leucurus
Rabbit (cottontail)..Sylvilagus floridanus
Raccoon…………Procyon lotor
Skunk …………...Mephitis mephitis
Squirrel (gray) …...Sciurus carolinensus
Squirrel (red) ….Tamiasciurus hudsonicus
Wolf ………….....Canis lupus
Woodchuck……...Marmota monax
Cat (domestic) …...Felis catus
Cattle (domestic) …Bos taurus
Chicken (domestic)..Gallus gallus
Dog (domestic) …...Canis familiaris
Duck (mallard) ……Anas platyrhynchos
Goat (domestic) …..Capra hircus
Goose (Canada) ..…Branta canadensis
Goose (domestic) …Anser anser
Horse (domestic) ….Equus caballus
Pig (domestic) …….Sus scrofa
Pigeon (domestic).....Columba livia
Sheep (domestic) …Ovis aires
Turkey ………... ....Meleagris gallopavo
More >> |
|
NISP
Number of Identifiable Specimens. Also termed Total Number of Fragments
(TNF). TNF or NISP calculations have been used to estimate relative
abundance of species. Recent research has shown that NISP calculations
are taphonomically erroneous and generally misleading. However,
given NISP's past popularity, this calculation is necessary for
comparison with previously analyzed assemblages.
MNI
Minimum Number of Individuals. The most common method of illustrating
the constituents of an assemblage is through a calculation of the
minimum number of individuals that would have to have existed to
create a given sample. There are numerous means of calculating this
number and the method selected is usually based on the type of assemblage.
MNI is generally determined by counting and siding the most frequent
element in an assemblage. For example, an assemblage with 13 tibias
suggests that minimally 7 individuals are represented by the assemblage.
Using element siding, 13 left tibias would suggest that minimally
13 individuals are represented.
Other Calculations
MNE=Minimum Number of an Element
MAU=Minimum Number of Animal Units
MGUI=Modified General Utility Index
FUI=Food Utility Index
MUI=Meat Utility Index
|
|