A taphonomic analysis of a multitaxic bonebed from the St. Mary River Formation (uppermost Campanian to lowermost Maastrichtian) of Alberta, dominated by cf. <i>Edmontosaurus regalis</i> (Ornithischia: Hadrosauridae), with significant remains of <i>Pachyrhinosaurus canadensis</i> (Ornithischia: Ceratopsidae)
Bibliographic record
Abstract
Scabby Butte is an isolated exposure of Upper Cretaceous (uppermost Campanian to lowermost Maastrichtian) strata of the St. Mary River Formation. These rocks have produced a diverse assemblage of both terrestrial and aquatic vertebrates, although hadrosaurid and ceratopsid dinosaurs represent the largest component by volume. Almost all of these dinosaur remains were collected from a single bonebed (Site 2) at Scabby Butte and have been referred to the hadrosaurid Edmontosaurus regalis Lambe, 1917 and the ceratopsid Pachyrhinosaurus canadensis Sternberg, 1950. This study presents a quantitative taphonomic reanalysis of the originally published data, providing new information previously overlooked and important information about the age-class structure of the dinosaur fauna preserved at the site. Site 2 is a lag deposit with a minimum number of 11 individuals (two ceratopsid, nine hadrosaurid), with three-quarters of the material being adult-sized based on size-class analysis. Most elements have undergone moderate to severe breakage and abrasion, and are completely disarticulated, suggesting that they were transported from where they died; post-mortem scavenging is also a possibility, as evidenced by the presence of tooth marks and trample marks on several elements. Burial took place soon after scavenging, as there is little evidence of subaerial weathering.
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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 | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 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".