A morphometric analysis of the lungs of high‐altitude ducks and geese
Bibliographic record
Abstract
Abstract We examined the morphology of the lungs of five species of high‐altitude resident ducks from Lake Titicaca in the Peruvian Andes (yellow‐billed pintail [ Anas georgica ], cinnamon teal [ Anas cyanoptera orinomus ], puna teal [ Anas puna ], speckled teal [ Anas flavirostris oxyptera ], and ruddy duck [ Oxyura jamaicensis ferruginea ]) and compared them with those of the high‐altitude migratory bar‐headed goose ( Anser indicus ) and the low‐altitude migratory barnacle goose ( Branta leucopsis ). We then determined the relationship between mass‐specific lung volume, the volume densities of the component parts of the lung, and previously reported hypoxia‐induced increases in pulmonary O 2 extraction. We found that the mass‐specific lung volumes and the mass‐specific volume of the exchange tissue were larger in the lungs of high‐altitude resident birds. The bar‐headed goose had a mass‐specific lung volume that fell between those of the low‐altitude species and the high‐altitude residents, but a mass‐specific volume of exchange tissue that was not significantly different than that of the high‐altitude residents. The data suggest that the mass‐specific volume of the lung may increase with evolutionary time spent at altitude. We found an inverse relationship between the percentage increase in pulmonary O 2 extraction and the percentage increase in ventilation across species that was independent of the volume density of the exchange tissue, at least for the resident Andean birds.
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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 | 0.001 |
| 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 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".