Phylogeography and population genomics of the American black bear (ursus americanus)
Bibliographic record
Abstract
The American black bear (Ursus americanus) is one of the eight living species of Ursidae, and the only one to have speciated in North America (1.8 - 1.2 Mya). This dissertation investigates the contemporary population structure of American black bears across their range; and specifically asks how a translocation of bears affected the population genetics of individuals in the Central Interior Highlands. Black bear mitochondrial lineages began forming within the last 170 kya, whereas the eastern and western nuclear genomes diverged 67 kya. A third nuclear lineage was discovered in contemporary Alaska, which diverged from the eastern lineage 31 kya. These three lineages harbor nine genetic clusters, and potentially more in unsampled portions of the range. These nine clusters may represent evolutionary significant units for the species; however, more work would be needed before proposing taxonomic revisions. The regional population genetics of the Central Interior Highlands (Arkansas, Oklahoma, and Missouri, USA) showed that the majority of genetic diversity in contemporary populations of the Ozark and Ouachita Mountains was introduced from Minnesota, USA and Manitoba, Canada during a translocation of bears from 1958 - 1968. Analyses also indicated that the contemporary Ozark and Ouachita populations were genetically differentiated. Additionally, bears that form a low diversity genetic cluster in Missouri were highly similar to bears from the Ozarks in genomic analyses, indicating a small founding population dispersed northwards following the reintroduction. Finally, I analyzed the accuracy and precision with which the natal location of a black bear may be identified using different inference methods and dataset compositions. While samples were estimated within 201 km of their sample site and with high precision, there was a low correlation between the state or province of sampling and that estimated. These results suggest caution when using genetic data for natal inference problems in cases for trade of wildlife products.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.000 | 0.001 |
| 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) | 0.001 | 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".