Microconchid tubeworms (Class Tentaculita) from the Joggins Formation (Pennsylvanian), Nova Scotia, Canada
Bibliographic record
Abstract
Microconchids have been described from the classic Pennsylvanian locality at Joggins, Nova Scotia. These encrusting tentaculitoid tubeworms have previously been mentioned and described from Joggins under the polychaete genus Spirorbis. Detailed morphological and microstructural investigation revealed that they belong to the species Microconchus carbonarius Murchison, confirming the previous tentative assignment (as Spirorbis carbonarius) made by Sir J. William Dawson in the nineteenth century. The occurrence of the same species in Upper Carboniferous deposits of England provides evidence supporting a connection between England and Nova Scotia in the Late Carboniferous (Pennsylvanian). Migration of the species could have been possible via brackish seas connecting both areas during maximum sea level during the Pennsylvanian. The species inhabited retrograding poorly drained coastal plain and open-water brackish environments, encrusting bivalve shells and plant remains in both sandstone and limestone deposits. Their high density (up to 19 individuals/cm2) may have resulted from their aggregative behaviour, high fecundity, and a lack of any competition with other skeleton-bearing encrusters. The large number (34%) of regenerated tubes indicates that microconchids were often preyed upon by associated animals, most probably fishes, which could graze on their dense encrusting aggregations.
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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 | 0.002 | 0.002 |
| Science and technology studies | 0.003 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".