ArticleEcology and evolution2021
Large brain size is associated with low extra-pair paternity across bird species.
Article in Ecology and evolution, 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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Who cites it
4 citing papers in PubMed.
- Energy Constraints and Ecological Adaptation Drive Divergent Evolution of Sensory and Cognitive Brain Regions in Bats.Integrative zoology · 2026Article
- Cooperative breeding and the selection for information sharing among groupmates.Behavioral ecology and sociobiology · 2025Article
- Problems with using comparative analyses of avian brain size to test hypotheses of cognitive evolution.PloS one · 2022Article
- Large brain size is associated with low extra-pair paternity across bird species.Ecology and evolution · 2021Article
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4 authors.
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Abstract
backgroundGaining extrapair copulations (EPCs) is a complicated behavior process. The interaction between males and females to procure EPCs may be involved in brain function evolution and lead to a larger brain. Thus, we hypothesized that extrapair paternity (EPP) rate can be predicted by relative brain size in birds. Past work has implied that the EPP rate is associated with brain size, but empirical evidence is rare.
methodsWe collated data from published references on EPP levels and brain size of 215 bird species to examine whether the evolution of EPP rate can be predicted by brain size using phylogenetically generalized least square (PGLS) models and phylogenetic path analyses.
resultsWe found that EPP rates (both the percentage EP offspring and percentage of broods with EP offspring) are negatively associated with relative brain size. We applied phylogenetic path analysis to test the causal relationship between relative brain size and EPP rate. Best-supported models (ΔCICc < 2) suggested that large brain lead to reduced EPP rate, which failed to support the hypothesis that high rates of EPP cause the evolution of larger brains.
conclusionThis study indicates that pursuing EPCs may be a natural instinct in birds and the interaction between males and females for EPCs may lead to large brains, which in turn may restrict their EPC level for both sexes across bird species.
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