Effects of surface activity patterns and dive depth on thermal substitution in fasted and fed lesser scaup (<i>Aythya affinis</i>) ducks
Bibliographic record
Abstract
High thermoregulation costs incurred by aquatic endotherms can be reduced if heat from digestion and exercising muscles can substitute for thermogenesis. Costs (VO2) of surface activities and diving were measured in lesser scaup (Aythya affinis (Eyton, 1838)) ducks while fasted and when feeding on mixed grain at depths of 1.2 and 2 m at thermoneutral (23 °C) and sub-thermoneutral (8 °C) water temperatures. Substitution occurred if the heat increment of feeding (HIF) or costs of activities above resting metabolic rate (RMR) were lower at 8 °C than at 23 °C, indicating that the thermoregulatory part of RMR at 8 °C had been reduced. Changes in body core temperature were not significant, and there was no substitution of HIF. At the surface at 8 °C, fasted birds that were active (nonresting) >75% of the time had lower RMR, and lower cost of activities above RMR, than less active birds. Dive recovery cost after dive bouts (DRC) constituted 33%–35% of total dive costs at 23 °C and 48%–55% at 8 °C. Dive costs above RMR (including DRC) were lower at 8 °C than at 23 °C by 14% at 1.2 m and 25% at 2 m, suggesting appreciable substitution that increased with longer, deeper dives; however, results varied widely and were not statistically significant. Our experiments indicate that thermal substitution varies in importance depending on levels of activity and heat loss.
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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 | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 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".