Evolutionary classification of the coiled Upper Cretaceous (turonian-Lower Campanian) planktic foraminifera with simple-ridged test wall
Bibliographic record
Abstract
Taxonomic revision of the Late Cretaceous (Turonian-early Campanian) planktic foraminiferal genus Hillsella Georgescu, 2008a results in its upgrading from typological genus to branched lineage, a unit that can be used in evolutionary classification. It consists of three species, H. hillsi Georgescu, 2008a, H. elongans new species, and H. planispiralis new species, which are characterized by simple–ridged test wall and probably evolved from Hedbergella planispira (Tappan, 1940). The earliest species of Hillsella, H. hillsi, exhibits trochospiral tests and globular chambers throughout the ontogeny. The first adaptive radiation from H. hillsi resulted in the evolution of H. elongans of the latest Turonian, which presents elongate chambers with one distal bulbous projection in the adult stage. The second adaptive radiation resulted in the evolution of H. planispiralis in the early Campanian, a globular chambered species with planispirally coiled test. Hillsella became extinct below the lower Campanian/middle Campanian boundary. The remarkable homogeneity in the test ultrastructure, porosity characteristics, and high variability in the gross test architecture challenges the validity of typological classification framework in use.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 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".