Intact genetic structure and high levels of genetic diversity in bottlenecked sockeye salmon (<i>Oncorhynchus nerka</i>) populations of the Fraser River, British Columbia, Canada
Bibliographic record
Abstract
Analysis of six microsatellite loci in 5800 sockeye salmon (Oncorhynchus nerka) from 29 Fraser River pop- ulations provided little evidence of genetic bottlenecks or mass straying in upper Fraser sockeye salmon resulting from reduced abundances following 1913-1914 rockslides in the Fraser canyon and successive decades of high exploitation. Upper Fraser populations were not characterized by a paucity of rare alleles, a sensitive indicator of populations in which effective size has been recently reduced. Heterozygosity and allelic diversity did not differ consistently between lower and upper Fraser populations. Throughout the watershed, early-migrating populations had lower allelic diversity and a lower proportion of rare alleles than did late-migrating ones. Genetic differentiation between upper and lower Fraser populations and heterogeneity among lower Fraser populations supported the suggestion that Fraser sockeye salmon are descendants of at least two postglacial races. Variation among lakes within regions was the strongest component of genetic structure, accounting for five times the variation among populations within lakes and more than two times the variation among regions. Extensive historical transplants of eggs and juveniles apparently resulted in lit- tle gene flow among regions, but three populations were reestablished or rebuilt as the result of more recent transplants. Resume : L'analyse des locus microsatellites chez 5800 saumons rouges (Oncorhynchus nerka) provenant de 29 popu- lations du Fraser a donne peu d'indications de l'existence de goulots d'etranglement genetiques ou de vagabondage en masse parmi les saumons rouges du cours superieur du Fraser a la suite des reductions de l'abondance causees par les eboulements survenus dans le canyon du Fraser en 1913-1914, puis par des decennies successives de forte exploitation. Les populations du cours superieur du Fraser ne se caracterisaient pas par un appauvrissement en alleles rares, ce qui constitue un indicateur sensible des populations chez lesquelles l'effectif a ete reduit depuis peu. L'heterozygotie et la diversite allelique ne differaient pas de facon constante entre les populations du cours superieur et du cours inferieur du Fraser. Partout dans le bassin, les populations a migration hâtive presentaient une diversite allelique et une propor - tion des alleles rares plus faibles que les populations a migration tardive. La differenciation genetique des populations du cours superieur et du cours inferieur du Fraser et l'heterogeneite des populations du cours inferieur du fleuve peu - vent confirmer que les saumons rouges du Fraser sont les descendants d'au moins deux « races » post-glaciaires. La variation entre les lacs au sein des regions etait la composante la plus forte de la structure genetique, et elle represen - tait cinq fois la variation parmi les populations au sein des lacs, et plus de deux fois la variation entre les regions. Les importantes transplantations d'oeufs et de juveniles effectuees dans le passe semblent avoir produit peu de flux genique entre les regions, mais trois populations ont ete retablies ou reconstituees par suite de transplantations plus recentes. (Traduit par la Redaction) Withler et al. 1998
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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 | 0.000 |
| 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) | 0.000 | 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".