Cardiorespiratory and metabolic changes during hypoxic flight in bar‐headed geese (879.20)
Bibliographic record
Abstract
The bar‐headed goose ( Anser indicus ) undergoes a biannual migration over the Himalayas, sustaining aerobic flight above 6,000 meters. The goal of our study was to collect cardiorespiratory and metabolic data during flight from geese flying in a wind tunnel in normoxia and two levels of hypoxia simulating altitude. In birds at rest, metabolic rate fell from 26.6 ± 1.3 mL min ‐1 kg ‐1 to 10.0 ± 0.9 mL min ‐1 kg ‐1 and 10.7 ± 4.8 mL min ‐1 kg ‐1 in normoxia, 10.5% O 2 and 7% O 2 respectively. It rose to 209.8 ± 5.2 mL min ‐1 kg ‐1 during flight in normoxia but decreased to 181.7 ± 5.0 mL min ‐1 kg ‐1 in 10.5% O 2 and to 131.7 ± 7.1 mL min ‐1 kg ‐1 in birds during flight in 7% O 2 . We found no change in heart rate across oxygen levels at rest or in flight. Heart rate at rest averaged 116.3 ± 35.4. While in flight, for any given metabolic rate we found a large range of heart rates in some individuals (184.5 to 457.0) and a very small range of heart rates in other individuals (256.8 to 375.7). There was, however, a strong positive correlation between metabolic rate and O 2 pulse (stroke volume x arterial‐venous O 2 content difference) at rest (slope=109.71; R 2 =0.57635) and in flight (slope=187.27; R 2 =0.65285) independent of the level of inspired O 2 in all birds. It appears that the bar‐heads increase metabolic efficiency during hypoxic flight and match O 2 supply to O 2 demand by a general increase in heart rate and specific increases in O 2 pulse. Grant Funding Source : NSERC of Canada; NSF, USA
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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 | 0.000 | 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 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".