Fitness costs and benefits of cowbird egg ejection by gray catbirds
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Gray catbirds (Dumetella carolinensis) eject over 95% of brown-headed cowbird (Molothrus ater) eggs placed into their nests. Ejection behavior could be maintained by selection from either: (1) cowbird parasitism, if the costs of accepting a cowbird egg outweigh the costs of ejecting it, or (2) conspecific parasitism, if such parasitism occurs naturally and results in ejection. This study tested the above hypotheses by measuring the cost of acceptance of cowbird parasitism (n 38 experimentally introduced cowbird chicks) and of cowbird egg ejection (n 94 experiments), as well as the frequency of natural conspecific parasitism among 229 catbird nests observed and the frequency of conspecific egg ejection (n 27 experiments). The conspecific parasitism hypothesis was not supported because catbirds accepted all foreign conspecific eggs placed into their nests, and no natural conspecific brood parasitism was detected at any nests. The cowbird parasitism hypothesis was strongly supported because the cost of accepting a cowbird chick (0.79 catbird fledglings) is much greater than the cost of ejecting a cowbird egg (0.0022 catbird fledglings per ejection).
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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) | 0.003 | 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 it