DINOSAUR DEATH PITS FROM THE JURASSIC OF CHINA
Bibliographic record
Abstract
Abstract Three newly discovered bonebeds from the Shishugou Formation of Xinjiang, China, are unusual in preserving vertically stacked and articulated to associated skeletons of at least 18 small, non-avian theropod dinosaurs in pits that are 1–2 m deep. The pits host a soft sediment-deformed mixture of alluvial and volcanic mudstone and sandstone. There is no evidence that the pits were discrete depressions in the topography that filled through time. Rather, they appear to have been highly localized areas of liquefaction caused by large-dinosaur (possibly sauropod) trampling of saturated sediments. Evidence indicates that the small theropods, and some other small vertebrates, became mired and died in these mud-filled pits. High quality skeletal preservation suggests that most individuals were buried within days to months after their deaths. Carcasses were buried successively, coming to rest above previously buried individuals. In some cases, skeletal body parts became separated or were removed, probably during scavenging. Given the large sizes of the pits relative to the small body sizes of the vertebrates contained within them, we conclude that small vertebrates (<3 m long and <1 m tall) were particularly susceptible to miring at these sites. Although the small, presumably herbivorous ceratosaur, Limusaurus inextricabilis, dominates the combined small theropod assemblage from these bonebeds (minimum number of individuals [MNI] = 15), there is no evidence that any biological features other than its small size and a large, and possibly, gregarious local population were responsible for its becoming mired in large numbers. A bias for small theropods in these bonebeds, compared to their relatively low abundance in the overall Shishugou Formation fauna, underscores that small theropods are underrepresented in Mesozoic fossil assemblages collected from other ancient alluvial and paludal settings.
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 | 0.002 | 0.002 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 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".