A holocene n-alkane stable isotope record from Wonderwerk Cave, South Africa and its implications for the later stone age record
Bibliographic record
Abstract
Abstract Sediment biomarkers are important archives of regional, and global climate signatures, particularly in regions which lack continuous terrestrial archives such as the semi-arid deserts of Africa. We measured carbon and hydrogen stable isotopes from plant wax n-alkanes recovered from the Holocene Later Stone Age (LSA) sedimentary sequence at Wonderwerk Cave (South Africa), that comprises several technocomplexes (Kuruman/Oakhurst, Wilton, Ceramic Wilton and Historic). The plant wax n-alkane results were integrated with published palaeoenvironment reconstructions from the cave based on faunal, botanical, geological and sedimentological proxies which provides a robust comparative framework. The findings match well with other proxy records from the same strata and indicate a semi-arid to semi-humid early Holocene, with a mix of woody C3 plants and C4 grasses. In contrast, the mid-late Holocene environment was increasingly arid, open and dominated by C4 grasses. A distinct humid period at 5300–6200 cal. BP is evident, associated with a high density of archaeological material and a change in cultural expression in the Wonderwerk record. This study provides a step forward in using stable isotopes from biomarkers to create terrestrial environmental records in semi-arid regions.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".