The Pennsylvanian tropical biome reconstructed from the Joggins Formation of Nova Scotia, Canada
Bibliographic record
Abstract
The Pennsylvanian (Langsettian) Joggins Formation contains a diverse fossil assemblage, first made famous by Lyell and Dawson in the mid-19th century. Collector curves based on c . 150 years of observation suggest that the Joggins fossil record is relatively complete. A key feature of the site is that fossils occur in (par)autochthonous assemblages within a narrow time interval (<1 Ma). Analysis of co-occurring taxa within a precise facies context permits ecosystem reconstruction, and three main communities are recognized in this study. Brackish seas, the distal extension of European marine bands, were populated by Foraminifera, molluscs, annelids, arthropods, fishes, and aquatic tetrapods. Poorly drained coastal plains were covered by rainforests of lycopsids, calamiteans, ferns, pteridosperms, and cordaitaleans, inhabited by a terrestrial fauna of molluscs, annelids, arthropods, and tetrapods, including the earliest known reptiles. Well-drained alluvial plains were covered by fire-prone cordaitalean scrub containing a low-diversity fauna of molluscs, arthropods, and tetrapods, locally preserved in waterholes. These three environments repeatedly interchanged with one another in response to base-level fluctuations forced by tectonism and glacioeustasy. Located further inland than other well-studied Pennsylvanian tropical sites, the Joggins Formation is significant because it contains a record of intra-continental terrestrial ecosystems.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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 teacher head, 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".