Abstract Increasingly researchers have employed confocal microscopy and 3D surface texture analysis to assess bone surface modifications in an effort to understand ancient behavior. However, quantitative comparisons between the surfaces of purported archaeological bone tools and experimentally manufactured and used bones are complicated by taphonomic processes affecting ancient bone. Nonetheless, it may be reasonable to assume that bones within the same deposits are altered similarly and thus these alterations are quantifiable. Here we show how unworked bones can be used to quantify the taphonomic effect on bone surfaces and how this effect can then be controlled for and incorporated into an analysis for evaluating the modified surfaces of purported bone tools. To assess the baseline taphonomy of Middle Paleolithic archaeological deposits associated with typologically identified bone artifacts, specifically lissoirs , we directly compare the surface textures of ancient and modern unworked ribs. We then compare the ancient unworked ribs and lissoirs to assess their differences and predict the ancient artifacts’ original surface state using a multilevel multivariate Bayesian model. Our findings demonstrate that three of five tested surface texture parameters ( Sa , Spc , and IsT ) are useful for distinguishing surface type. Our model predictions show that lissoirs tend to be less rough, have more rounded surface peaks, and exhibit more directionally oriented surfaces. These characteristics are likely due to anthropogenic modifications and would have been more pronounced at deposition. Quantifying taphonomic alterations moves us one step closer to accurately assessing how bone artifacts were made and used in the ancient past.
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Non-destructive ZooMS identification reveals strategic bone tool raw material selection by Neandertals
Abstract Five nearly identical fragments of specialized bone tools, interpreted as lissoirs (French for “smoothers”), have been found at two Middle Paleolithic sites in southwest France. The finds span three separate archaeological deposits, suggesting continuity in the behavior of late Neandertals. Using standard morphological assessments, we determined that the lissoirs were produced on ribs of medium-sized ungulates. However, since these bones are highly fragmented and anthropogenically modified, species determinations were challenging. Also, conservative curation policy recommends minimizing destructive sampling of rare, fragile, or small artifacts for molecular identification methods. To better understand raw material selection for these five lissoirs , we reassess their taxonomy using a non-destructive ZooMS methodology based on triboelectric capture of collagen. We sampled four storage containers and obtained identifiable MALDI-TOF MS collagen fingerprints, all indicative of the same taxonomic clade, which includes aurochs and bison ( Bos sp. and Bison sp.). The fifth specimen, which was stored in a plastic bag, provided no useful MALDI-TOF MS spectra. We show that the choice of large bovid ribs in an archaeological layer dominated by reindeer ( Rangifer tarandus ) demonstrates strategic selection by these Neandertals. Furthermore, our results highlight the value of a promising technique for the non-destructive analysis of bone artifacts.
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- Award ID(s):
- 1550161
- NSF-PAR ID:
- 10409951
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41598-020-64358-w
