ArticlePeerJ2021
The effects of parental age difference on the offspring sex and fitness of European blackbirds.
Article in PeerJ, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.
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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.
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Who cites it
4 citing papers in PubMed, 7 citations in OpenAlex.
- Persistent maternal age effects on male offspring fitness traits in a wild mammal population.Evolution letters · 2025Article
- Is the sex ratio of Japanese quail offspring equal?Tropical animal health and production · 2024Article
- Adoption and feeding of fieldfare nestlings and fledglings by European blackbird.Ecology and evolution · 2023Article
- Separating the effects of paternal age and mating history: Evidence for sex-specific paternal effect in eastern mosquitofish.Evolution; international journal of organic evolution · 2022Article
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Authors and funding
6 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundMany studies of birds have indicated that offspring sex ratios can vary with environmental and parental traits. On the basis of long-term research, we first evaluated the possible influence of parental age difference and brood characteristics on offspring sex and fitness in multi-brooded Blackbirds METHODOLOGY: The study was conducted in the city-centre Stefan Żeromski Park in Szczecin, NW Poland, where the local population of Blackbirds has been studied since 1996. Data on the offspring sex and fitness were collected in five years, 2005-2007 and 2016-2017. During the breeding season we inspected the study area to locate the pairs' territories and to track their nests and clutches.
resultsWe found that the overall sex ratio did not differ statistically from 50:50, but that younger females bonded with older mates did tend to produce more sons, probably because of the greater fitness of male descendants. Accordingly, the sons' breeding success increased with the father's age, but this relationship was close to non-linear, which may indicate that the transgenerational effect of paternal senescence could negatively affect progeny fitness despite the high-quality of older fathers. Older females mated with younger males produced more daughters, which could have been due to the lesser attractiveness of the males and the mothers' poorer condition caused by accelerated senescence. We found that neither offspring hatching sequence nor hatching date or clutch sequence were significant for sex determination.
conclusionsWe consider that in our Blackbird population, parental age could make a more significant contribution to shaping offspring sex and reproductive success.
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