Cryptic population structure in the severely depleted cowcod,<i>Sebastes levis</i>
Bibliographic record
Abstract
Cowcod (Sebastes levis) is a member of a northeastern Pacific Ocean species flock that experienced extensive fishery exploitation. Factors that could produce structure in cowcod include a major biogeographic boundary within cowcod’s geographical distribution; severe declines in abundance, potentially, resulting in reductions in effective population size and divergence owing to genetic drift; and dependence on patchily distributed habitat. We examine the following two questions: (i) is there subdivision present and, if so, is it concordant with the two marine biogeographic regions separated by Point Conception, and (ii) have cowcod experienced loss of genetic variation owing to population size reduction? Coarse-scale genetic and otolith analyses indicated regional structure across Point Conception. However, analysis of 24 microsatellite DNA loci revealed as many as three cryptic, divergent lineages (FCT= 0.194) that meet south of Point Conception. The two southern lineages had higher growth rate than the northerly distributed lineage. In general, cowcod is the least genetically diverse of ∼10 rockfishes surveyed with the same markers, but the recent substantial declines in abundance were not reflected by recent genetic bottleneck analyses.
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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 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".