ANT-309 Elements of Archaeology Lecture Outline February 18, 2008

VIII Interpreting Ecofacts: Reconstructing Subsistence and Past Environments

A Subsistence: The Quest for Food

B Reconstructing past environments with non-archaeological data

1 Paleoclimate

a Physical Evidence

i Sea and lake levels

ii Extent of glaciers (moraines) and ice caps

b Biological evidence of climate change; for example, variation in:

i Fauna (fossil bone assemblages)

ii Vegetation

(a) Pollen (palynology)

(b) Plant macro-fossils in peat,

(c) Pack rat nests

c Chemistry of atmosphere and sea water

i Oxygen isotope analysis

C Environmental reconstruction from archaeological data: Human interaction with the physical and biological environment creates archaeological sites

1 “Sampling” of the environment is likely to be strongly biased

2 Mixing of cultural and natural materials can cause problems

D Inferring subsistence from the archaeological record

1 Artifacts may provide indirect clues

2 Better subsistence indicators:  residues and waste products from food preparation (ecofacts)

a Floral remains Reflect both prehistoric environment and prehistoric diet: Very important to determine the context of the remains, ie., natural or anthropogenic deposition.

i Macrofossils

(a) Wood (rare)- Monte Verde

(b) Charred Seeds

(c) Coprolites

ii Microfossils

(a) Phytoliths

(b) Pollen

iii Floral sampling

(a) Fine mesh screen, limited volume of sediment

(b) Column samples

(c) Feature samples

(d) Off site samples (control samples)

(e) Recovery techniques: Flotation (Most samples lighter than water)

b Faunal analysis

i Species identification - comparison with modern reference collections

ii sometimes hard to distinguish bones and shells deposited by natural and anthropic processes

iii While presence in the archaeological record usually implies that an animal was living in the area of the site, absence doesn’t mean the animal was absent from the environment.

iv Calculate NISP (Number of Identified Specimens) use raw bone counts per species as indicators of relative frequency of species i.e. 100 rabbit bones and 5 California sea lion bones may indicate that that rabbits were 20x more important that sea lions- or not

v Calculate MNI (Minimum Number of Individuals) If bones are very fragmented or eroded, one may only be able to place bones in size classes (very large, large, medium, small, very small). This still may produce useful data.

(a) problem is that there may be relatively few individuals of a species but many bone fragments because of the way they were processed.

(b) Tabulate bone frequency by element per species: If you have 4 left femurs from California sea lion you know you have at least 4 individuals

1. Quite difficult if bone assemblage is very large and bones are highly fragmented

2. Analysis of large, fragmented assemblage may produce inflated results; example, four sea lion femurs could be so fragmented, you wouldn’t be able to tell how many femurs were actually present.

vi Examine bones for cut marks and scrapes indicating butchering strategies

vii Lewis Binford suggested that bones can indicate variable utility of body parts Binford derived General Utility Index (GUI) of body parts from study of Nunamiut hunter-gatherers

(a) different elements offer more value than others; ie., upper limbs have more meat than lower limbs, or extremities ; horns and antlers have no caloric value

(b) rank ordered elements by percent weight of attached meat, marrow and grease.

(c) Binford used these ideas to think about different types of utility strategies:

(i) Unbiased Utility Strategy:transport body parts (including bones) from the butcher/kill site in direct proportion to their frequency in the body

(ii) Bulk Utility Strategy: transport of large quantities of high and moderate utility elements, discard only lowest utility parts

(iii)  Gourmet Utility Strategy: transport only those parts of extremely high utility, discarding the moderate and low utility elements.

ii Binford’s utility model offered means of anticipating and interpreting variability in bone assemblages

(i)  larger animals are seldom taken at or near residential sites where people live

(ii)  which utility strategy is employed and which parts are transported from kill sites is likely a function of utility of parts (benefit) and and costs given by terrain, transport distance, size of hunting party, likelihood of encounters w/ enemies, etc.

(iii) thus, a kill/butchering is more likely to contain bones of low utility parts (phalanges, vertebrae, horns, mandibles), while residential sites are more likely to contain higher frequencies of higher utility parts (ribs and the long bones)

iii Binford also compared prey bone assemblages of humans and animals

(i) What man transports animals generally leave behind, what animals leave at a kill humans will transport

(ii) must also consider differential survivability of different bones – taphonomy: The study of  what happens to animals (or plants) between the time they die and the time they are recovered archaeologically or found as a fossil