Neurocranial anatomy of<i>Seymouria</i>from Richards Spur, Oklahoma
Bibliographic record
Abstract
Seymouriamorphs are a group of Permo-Carboniferous tetrapods with both terrestrial and aquatic members. Since their initial discovery, they have been proposed as phylogenetic intermediates on the amniote stem between temnospondyl amphibians and crown amniotes and are thus frequently used in phylogenetic analyses of both early amniotes and, more broadly, Paleozoic tetrapods. We utilized neutron computed tomography (nCT) to study the morphology of the first cranial material of Seymouria from the early Permian karst deposits found at the Dolese Brothers Limestone Quarry near Richards Spur, Oklahoma. The presence of a mixture of purported autapomorphies of both of the better-known species of Seymouria, S. baylorensis and S. sanjuanensis, prevents referral to either species; the potential for ontogenetic variation in many of these characters highlights the need to reevaluate the taxonomy of these species. Our description of the tomographic data focuses on the braincase and otic capsule and helps to clarify details of previously poorly known neurocranial anatomy, such as an orbitosphenoid that expands dorsally to abut the overlying frontals. The prootic and the opisthotic are complex structures that preserve clear impressions of all three semicircular canals and that frame the laterally extensive otic tube and possibly the perilymphatic duct. Our analysis provides additional details regarding a previously described but poorly known ossification of the synotic tectum and highlights the ongoing uncertainty regarding the homology of such ossifications across Paleozoic tetrapods.
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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 | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| 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".