Offspring growth and parental care in sexually dimorphic Nazca boobies (Sula granti)
Bibliographic record
Abstract
A review of studies on nestling bird food requirements indicates that degree of sexual size dimorphism reliably predicts disparity in sex-specific food requirements, but that parents often fail to meet the excess requirement of the larger sex. We studied a population of Nazca boobies ( Sula granti Rothschild, 1902), a sexually dimorphic pelagic seabird, to determine whether parents provide more care to daughters, the larger sex. Daughters grew to a larger size than did sons during the nestling period, but did not reach the mean size of adult females, while sons exceeded the size of adult males. Estimates of parental effort exerted for sons versus daughters indicated similar levels of effort, and that females fledged in poorer condition than males did in the study year, one of intermediate breeding conditions. Results from another study conducted during better breeding conditions indicated little limitation on growth of either sex. Together, these studies are consistent with a ceiling on parental effort in a long-lived species that allows consistent self-maintenance for parents, but causes poor performance in the costlier sex under poor breeding conditions. Complementary studies of short-lived species are needed to evaluate our suggested linkage between parental effort, self-maintenance, and sexual size dimorphism.
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 | 0.001 | 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) | 0.001 | 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 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".