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Documenting Differences between Early Stone Age Flake Production Systems: An Experimental Model and Archaeological Verification.

Presnyakova D, Archer W, Braun DR, Flear W - PLoS ONE (2015)

Bottom Line: Thickness evenness and curvature had the greatest effect sizes in both the Generalized Linear and Discriminant models.Interestingly the interaction between thickness evenness and platform depth was significant and played an important role in influencing technological group membership.The results of the discriminant function analysis demonstrate that the majority of flakes at the Cutting 10 locality were not associated with the production of the numerous Large Cutting Tools found at the site, which corresponds with previous suggestions regarding technological behaviors reflected in this assemblage.

View Article: PubMed Central - PubMed

Affiliation: Department of Early Prehistory and Quaternary Ecology, University of Tübingen, Schloss Hohentübingen, Tübingen, Germany.

ABSTRACT
This study investigates morphological differences between flakes produced via "core and flake" technologies and those resulting from bifacial shaping strategies. We investigate systematic variation between two technological groups of flakes using experimentally produced assemblages, and then apply the experimental model to the Cutting 10 Mid -Pleistocene archaeological collection from Elandsfontein, South Africa. We argue that a specific set of independent variables--and their interactions--including external platform angle, platform depth, measures of thickness variance and flake curvature should distinguish between these two technological groups. The role of these variables in technological group separation was further investigated using the Generalized Linear Model as well as Linear Discriminant Analysis. The Discriminant model was used to classify archaeological flakes from the Cutting 10 locality in terms of their probability of association, within either experimentally developed technological group. The results indicate that the selected independent variables play a central role in separating core and flake from bifacial technologies. Thickness evenness and curvature had the greatest effect sizes in both the Generalized Linear and Discriminant models. Interestingly the interaction between thickness evenness and platform depth was significant and played an important role in influencing technological group membership. The identified interaction emphasizes the complexity in attempting to distinguish flake production strategies based on flake morphological attributes. The results of the discriminant function analysis demonstrate that the majority of flakes at the Cutting 10 locality were not associated with the production of the numerous Large Cutting Tools found at the site, which corresponds with previous suggestions regarding technological behaviors reflected in this assemblage.

No MeSH data available.


Related in: MedlinePlus

Thickness evenness coefficient.Arrows show points of percussion, whereas solid lines represent places on a flake where thickness was measured.
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pone.0130732.g003: Thickness evenness coefficient.Arrows show points of percussion, whereas solid lines represent places on a flake where thickness was measured.

Mentions: Thickness evenness coefficient (Fig 3): This variable captures variation in flake thickness along the technological length axis. Thickness was measured at 25%, 50%, and 75% of the technological length. The standard deviation was then calculated for these three values. Low values indicate that thickness measurements do not vary greatly along the technological axis whereas high values indicate substantial variation in thickness along the technological axis. High values may be explained by flakes where the volume is concentrated at one point in the flake (e.g. bulb of percussion). Maintenance of the bi-convex section of an LCT requires removals with a relatively evenly distributed thickness, thus Mode 2 flakes are more likely to have lower values. Eren and Lycett [101] documented similar patterns of thickness variation within an individual flake in other technologies where flake shape is maintained by the knapper [101].


Documenting Differences between Early Stone Age Flake Production Systems: An Experimental Model and Archaeological Verification.

Presnyakova D, Archer W, Braun DR, Flear W - PLoS ONE (2015)

Thickness evenness coefficient.Arrows show points of percussion, whereas solid lines represent places on a flake where thickness was measured.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4482428&req=5

pone.0130732.g003: Thickness evenness coefficient.Arrows show points of percussion, whereas solid lines represent places on a flake where thickness was measured.
Mentions: Thickness evenness coefficient (Fig 3): This variable captures variation in flake thickness along the technological length axis. Thickness was measured at 25%, 50%, and 75% of the technological length. The standard deviation was then calculated for these three values. Low values indicate that thickness measurements do not vary greatly along the technological axis whereas high values indicate substantial variation in thickness along the technological axis. High values may be explained by flakes where the volume is concentrated at one point in the flake (e.g. bulb of percussion). Maintenance of the bi-convex section of an LCT requires removals with a relatively evenly distributed thickness, thus Mode 2 flakes are more likely to have lower values. Eren and Lycett [101] documented similar patterns of thickness variation within an individual flake in other technologies where flake shape is maintained by the knapper [101].

Bottom Line: Thickness evenness and curvature had the greatest effect sizes in both the Generalized Linear and Discriminant models.Interestingly the interaction between thickness evenness and platform depth was significant and played an important role in influencing technological group membership.The results of the discriminant function analysis demonstrate that the majority of flakes at the Cutting 10 locality were not associated with the production of the numerous Large Cutting Tools found at the site, which corresponds with previous suggestions regarding technological behaviors reflected in this assemblage.

View Article: PubMed Central - PubMed

Affiliation: Department of Early Prehistory and Quaternary Ecology, University of Tübingen, Schloss Hohentübingen, Tübingen, Germany.

ABSTRACT
This study investigates morphological differences between flakes produced via "core and flake" technologies and those resulting from bifacial shaping strategies. We investigate systematic variation between two technological groups of flakes using experimentally produced assemblages, and then apply the experimental model to the Cutting 10 Mid -Pleistocene archaeological collection from Elandsfontein, South Africa. We argue that a specific set of independent variables--and their interactions--including external platform angle, platform depth, measures of thickness variance and flake curvature should distinguish between these two technological groups. The role of these variables in technological group separation was further investigated using the Generalized Linear Model as well as Linear Discriminant Analysis. The Discriminant model was used to classify archaeological flakes from the Cutting 10 locality in terms of their probability of association, within either experimentally developed technological group. The results indicate that the selected independent variables play a central role in separating core and flake from bifacial technologies. Thickness evenness and curvature had the greatest effect sizes in both the Generalized Linear and Discriminant models. Interestingly the interaction between thickness evenness and platform depth was significant and played an important role in influencing technological group membership. The identified interaction emphasizes the complexity in attempting to distinguish flake production strategies based on flake morphological attributes. The results of the discriminant function analysis demonstrate that the majority of flakes at the Cutting 10 locality were not associated with the production of the numerous Large Cutting Tools found at the site, which corresponds with previous suggestions regarding technological behaviors reflected in this assemblage.

No MeSH data available.


Related in: MedlinePlus