Egg-Laying Competition and Maternal Effects in a Plural-Breeding Joint-Nesting Bird
Bibliographic record
Abstract
I investigated the maternal effects that take place in a joint-nesting bird: the smooth-billed ani. Female anis were shown to respond to increasing group size by increasing the number of eggs produced per capita, by tossing and burying more eggs per capita, and by taking longer to reach the dedicated incubation phase. These results support the hypothesis that females respond to increased egg laying competition by trying to skew the contents of the final incubated clutch of eggs in their own favor. I showed that in ani groups, yolk testosterone and estradiol deposited by females in eggs increased from early- to late-laid eggs. Increases in yolk steroid levels over the laying sequence may function to mitigate the disadvantage of being a later-hatched chick. This maternal influence may not be a mere reflection of a female's hormonal status as female plasma circulating levels of testosterone and estradiol did not vary in the same direction as yolk hormone profiles. I showed that yolk corticosterone levels, an indicator of maternal physiological stress, increased with laying order in multi-female groups, but not in single-female groups. Results suggest that laying females experience higher levels of stress in multifemale groups. The above results suggest that communal life in anis generates competition and egg production waste that likely reduces short-term per capita reproductive benefits. Female anis can vary egg quality via deposition of hormones in eggs, and also lay eggs of different sizes. I showed that circulating plasma testosterone levels were higher in nestlings with better begging abilities. Furthermore, nestlings hatched from eggs laid late in the laying sequence had better begging abilities. These results suggest that testosterone is an important controlling mechanism of begging behaviour, and that female testosterone depositions in eggs rave long lasting effects on offspring development and behavior.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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) | 0.002 | 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".