Code and data from: Silver spoons, reproduction, and growth catch-up in eastern grey kangaroos
Bibliographic record
Abstract
Early growth and environmental conditions can shape life-history trajectories. Long-lived iteroparous species with indeterminate growth face growth-reproduction trade-offs for most of their lives. Poor early conditions can delay primiparity and restrict growth, potentially compensated for by faster growth later in life, at the cost of reduced reproduction. We explored the variation in age at primiparity and early reproduction in eastern grey kangaroos, based upon 13 years of monitoring about 100 known-age females. We then examined associations between early reproduction, later reproduction, lifetime growth. We used a modified von Bertalanffy growth function to model the indeterminate growth of females and to test the effects of early reproduction on lifetime growth. Favorable environmental conditions, large size, and condition as a subadult led to earlier reproduction and higher reproductive success at ages 3-5. As females aged, size and condition had diminishing effects on reproductive success. Females with greater early-adulthood reproduction had slightly higher reproduction later in life. We did not detect a growth cost of early reproduction. Large females in good condition favored early reproduction over growth, while those with poor early growth exhibited growth catch-up at the cost of reproduction both early and later in life. As reported for other long-lived iteroparous species with indeterminate growth, female kangaroos prioritize growth over reproduction for much of their lifespan. Eastern grey kangaroos show heterogeneity in early growth and reproductive strategies. Early primiparity and reproduction are constrained by body condition, size, and environmental conditions when females are pre-reproductive subadults.
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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 | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.002 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.001 |
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".