Triassic ichthyopterygian assemblages of the Svalbard archipelago: a reassessment of taxonomy and distribution
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Abstract Ichthyopterygians were amongst the most specialised lineages of secondarily aquatic amniotes; however, their origin and initial radiation remain obscure. The stratigraphically oldest and phylogenetically most basal taxa have been found in Early–Middle Triassic deposits throughout the northern hemisphere, but one of the earliest documented and arguably most important localities is the High Arctic Svalbard archipelago. Like many classic palaeontological sites, the Svalbard Triassic fossil-bearing horizons are plagued by inconsistent geological interpretations and taxonomic classifications. To resolve these conflicts, a comprehensive revision of the various ichthyopterygian assemblages was undertaken. The fossils were found to be distributed through three sequential rock units: the Olenekian Vikinghøgda Formation (six discernible taxa distributed over two distinct horizons), Anisian lower Botneheia Formation (two taxa) and the Ladinian–Carnian Blanknuten Member of the Botneheia Formation–Tschermakfjellet Formation (five taxa). Unfortunately, many of the specimens are non-diagnostic at species-level, although they do contribute a cohesive picture of marine faunal successions during the Early–earliest Late Triassic. Indeed, the Svalbard archipelago has produced one of the most diverse Early Triassic ichthyopterygian assemblages known worldwide, but is comparatively species poor throughout the early Middle Triassic, perhaps due to sampling biases. Keywords: IchthyosauriaSvalbard Grippia Vikinghøgda FormationBotneheia FormationTschermakfjellet Formation Acknowledgements The authors thank R. Schoch and J. Müller for logistical support and T. Scheyer for discussion. J.O. Ebbestad (Evolutionsmuseet, Uppsala Universitet), J. Hagstrom (Naturhistoriska Riksmuseet, Stockholm) and S. Kelly (Cambridge Arctic Shelf Programme) generously facilitated access to collections. The comments of two anonymous reviewers significantly improved the manuscript. This project was funded by the Palaeobiology Programme at Uppsala University, the Natural Sciences and Engineering Research Council of Canada (NSERC) and an Alexander von Humboldt Postdoctoral Fellowship (to EM).
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.
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 | 0.000 | 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 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 it