Sexual dimorphism of North American sturgeons, Acipenser species
Bibliographic record
Abstract
I have developed a technique to determine the sex of live adult sturgeons by examination of external morphology. I analyzed four North American sturgeon species: 'Acipenser transmontanus' (white sturgeon), ' A. oxyrhincus' (Atlantic sturgeon), 'A. medirostris' (green sturgeon) and 'A. brevirostrum' (shortnose sturgeon). The opening of the urogenital duct is posterior to the anus. Males have a urogenital opening with a capital Y-shape while females have an O-shaped opening. Accuracy of sex determination was highest in live fish (82%), but significantly lower in dead fish (29%). Dead sturgeon usually have the rectum prolapsed via the cloaca so the urogenital opening and surrounding fleshy tissue are protruded, thus making the sexes indistinguishable. I tested this technique with nai?ve field personnel and observers in the laboratory. Successful application of this technique requires training of both those taking observations on the fish and those interpreting resulting photographs.
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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 | 0.000 |
| 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) | 0.002 | 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".