Larval Life History of Coastal Tailed Frogs (Ascaphus truei) Across an Elevational Gradient in Northern California: Implications for a Changing Climate
Bibliographic record
Abstract
Coastal Tailed Frogs (Ascaphus truei) range across the Pacific Northwest from northern California, USA, into British Columbia, Canada, and from sea level to >2,131 m. Previous work has shown a variable larval period but has not clearly separated elevational from latitudinal effects. Therefore, we examined size at beginning of metamorphosis, larval period, individual growth rates, and timing of metamorphosis of A. truei populations along an elevational gradient from 152 to 2,131 m across a small latitudinal range (29 km) to reduce potential latitudinal effects, all within the Klamath Mountains of northern California. We sampled larvae at 15 study sites, of which we used 6 sites as intensive capture–mark–recapture (CMR) locations, and the other 9 for supplemental data on larval period and size at metamorphosis. In CMR sites, we individually marked tadpoles to determine within-season growth rates. We found that the A. truei larval period in these populations ranges from 2 yr in low and middle elevations to ‡3 yr in high-elevation populations. We also found decreased size at beginning of metamorphosis and increased growth rates of tadpoles with increasing elevation. Our high-elevation populations had the longest larval period documented in California. The associations of growth and timing of metamorphosis to elevation in A. truei populations suggest that responses to changing climate may differ across elevations.
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 | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 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".