3 - Techniques in Archaeobotany

microfossils

1. phytoliths 2. starch grain, 3. resin analysis 4. palynology

key analysis techniques of reconstruction of wet tropics

Macrofossil - toxic nut presence in archaeological sites (compared to stone tools found at the same sites) Charcoal - provides dating control Starch analysis - identifies what tools were used, and what types of nuts were processed Ethnographic data - discussion with elders about what nuts were used and how they were processes, historical photos and accounts

Cultural and environmental reconstructions

archaeobotany can be used to examine and reconstruct previous environments - example; the aboriginal societies in the Wet Tropics; examined toxic nuts and permanent occupation of the rainforest environment. relatively late ~2500 ya in response to El Nino intensification impacts on the regions leading to drier climates and altered vegetation patterns.

reasons for analysing macrofossils

can provide information on - food processing & palaeodiet - human adaptation & movements - environmental and plant management - vegetation history - taphonomic site history - can be used in radiocarbon dating (seeds & other organic material often the best type of material for C14 dating)

Charcoal analysis

charred materials often the most common material found in archaeological sites - humans are closely linked with fire! methods;; brought back from the site - directly collected, sieved, floated out of sediments. then sorted into size categories and examined under an electron microscope differences in the vascular tissue of taxa usually preserved - this is used to identify the taxa. compared to a modern reference collection.

residue analysis

involves looking at organic remains on tools to determine what plants humans were using (particularly relevant to starch and resin analysis). may also be used to examine phytoliths and pollen.

ethnographic data

involves the use of anthropological and historical data to examine past environmental changes. is a key resource in any projected looking to examine people - used to verify environmental records from other proxies. relevant data includes; indigenous plant use or knowledge, explorer/settler accounts, tax records, journals, historical accounts.

'starch grains'

microscopic components from various plant pats - generally storage organs eg tubers, buts and trunk piths. can be found in soil after plant dies - used to id taxa also found on tools - can be used to id what plants people were using. also used for C14 dating.

'Macrofossils'

plant remains collected from archaeological sites. methods: direct excavation, sieving of excavated materials, flotation of bulk samples. usually charred/hardy materials eg seeds, woods, stones & nut kernels (occasionally soft material may be preserved in correct conditions) macrofos assemblage (both intact and fragmented) are sorted and identified to genus or species level and compared with a reference collection.

relevance of plants to human society;

plants are a fundamental component of human economies; materials for food, medicine, clothing shelter & tools. there have been several major technological innovations associated with changes in plant use; agriculture, urbanisation, alterations in hunter-gatherer societies.

what can we discover from charcoal?

remember humans are closely linked with fire! provides insight into what humans were burning allowing - reconstruction of the surrounding environment - informs of changes in landscape associated with human exploitation - whether wood has been used for a particular purpose eg. smelting materials or for cultural practices

'phytoliths'

siliceous concretions that form in the intra and intercellular spaces of plants. when the plants decompose, the phytoliths remain in the soil. morphologies can be identified and linked to genus, species or family. generally better preserved in soil and in drier environments and can provide greater taxonomic resolution of key families (esp. pollen).

"archaeobotany"

the study of plan remains from archaeological sites (context. directly linked to people - focuses on how humans respond to env change, how societies change and impact on the environment. key analysis techniques: Macrofossil remains, microfossils; charcoal.

'resin analysis'

were commonly used as sealants, adhesives & fixatives inform about manufacture and function of tools - also thought to be socially and economically traded. examined using geochemistry.