VARIATION IN CAROTENOID-BASED COLOR IN NORTHERN FLICKERS IN A HYBRID ZONE
Bibliographic record
Abstract
We studied variation in the carotenoid color of flight feathers of hybrid Northern Flickers (Colaptes auratus) and its correlation with reproductive performance and survival. Color scores provided by a digital camera revealed in 218 individuals a continuous spectrum from yellow to red. Males tended to be slightly redder than females. Within individuals, an analysis of color change with age revealed that males, but not females, became redder with age. Except for yearling females, body condition did not improve with age, suggesting that color is not linked to body condition measured during incubation. We did not detect any correlations between feather color and measures of reproductive performance, such as clutch size, hatching success, or fledging success, or return rate to the study area. In a hybrid population where intraspecific variation in color is controlled partly by genes, hue or brightness may not be a useful signal of individual quality, contrary to other studies of birds. About 25% of flickers had one or more tail feathers that differed from the rest of the plumage. In each case, the “odd” feathers were paler or yellower in color and may have been caused by diet or stress when the feathers were lost and regrown during winter. Such odd colors support the hypothesis that red carotenoid pigments are costly to maintain under stressful conditions.
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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 | 0.000 |
| 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 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".