Phylogeography of the Pacific Sardine, Sardinops sagax, in the Northeastern Pacific
Bibliographic record
Abstract
The Pacific Sardine, (Sardinops sagax), is a small, coastal pelagic species in the family Clupeidae. Sardine are an ecologically important forage fish for many animals, including larger, economically and ecologically important fishes, and have historically supported an important commercial fishery. When the fishery declined in the 1940s, a massive effort in understanding population structure for the Pacific Sardine resulted in a wealth of literature. Initially, these studies agreed on a large panmictic population with high annual variation, but the general consensus has since been that there are multiple subpopulations of the Pacific Sardine along the West Coast of North America. However, there has been no molecular evidence that disparate groups exist within the Pacific Sardine in the Northeastern Pacific. Marine fishes often do not show deep population structure, and regional populations of Sardinops are subject to massive natural population fluctuations which often result in shallow gene lineages. Mitochondrial sequences are known for their rapid mutation rates as compared to nuclear gene sequences, thus are good indicators of population structure over evolutionary time scales. To test if population structure was apparent in Sardines, 434 individuals were examined ranging from Vancouver Island, British Columbia to Bahía Magdalena, Baja California, and a group from the Gulf of California. A 1062 bp fragment of the cytochrome b gene yielded extremely low but significant fixation rates for ɸST. Concordantly low fixation was observed for ɸCT, and was non-significant in all but one instance. These data support the null hypothesis of an absence of genetic structure in the Pacific Sardine.
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How this classification was reachedexpand
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 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 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 itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, 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".