SynthesiseLife2025
No evidence for a trade-off between reproduction and survival in a meta-analysis across birds.
Synthesis in eLife, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
7 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Trade-offs in avian parental care: a review of theory and meta-analysis of brood size manipulations.Biological reviews of the Cambridge Philosophical Society · 2026Pooled it
- From environmental perception to reproductive allocation: the microbiome-membrane-mitochondria axis in poultry.Poultry science · 2026Review
- Analysis of reproductive behavior in male pigeons in the White Mirthys and Egyptian Baladi breeds injected with testosterone propionate.BMC veterinary research · 2026Article
- Reproductive Drivers of Temporal Telomere Dynamics in Female Tree Swallows.Molecular ecology · 2026Article
- Lifetime fitness and annual survival are heritable and highly genetically correlated in a wild primate population.Evolution; international journal of organic evolution · 2026Article
- Lifetime fitness and annual survival are heritable and highly genetically correlated in a wild primate population.bioRxiv : the preprint server for biology · 2025Article
- Mothers facing greater environmental adversity experience increased costs of reproduction.Science advances · 2025Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors.
Funding
Abstract
Life-history theory, central to our understanding of diversity in morphology, behaviour, and senescence, describes how traits evolve through the optimisation of trade-offs in investment. Despite considerable study, there is only minimal support for trade-offs within species between the two traits most closely linked to fitness - reproductive effort and survival - questioning the theory's general validity. We used a meta-analysis to separate the effects of individual quality (positive survival/reproduction correlation) from the costs of reproduction (negative survival/reproduction correlation) using studies of reproductive effort and parental survival in birds. Experimental enlargement of brood size caused reduced parental survival. However, the effect size of brood size manipulation was small and opposite to the effect of phenotypic quality, as we found that individuals that naturally produced larger clutches also survived better. The opposite effects on parental survival in experimental and observational studies of reproductive effort provide the first meta-analytic evidence for theory suggesting that quality differences mask trade-offs. Fitness projections using the overall effect size revealed that reproduction presented negligible costs, except when reproductive effort was forced beyond the maximum level observed within species, to that seen between species. We conclude that there is little support for the most fundamental life-history trade-off, between reproductive effort and survival, operating within a population. We suggest that within species the fitness landscape of the reproduction-survival trade-off is flat until it reaches the boundaries of the between-species fast-slow life-history continuum. Our results provide a quantitative explanation as to why the costs of reproduction are not apparent and why variation in reproductive effort persists within species.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.