ArticlePloS one2022
Problems with using comparative analyses of avian brain size to test hypotheses of cognitive evolution.
Article in PloS one, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers.
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Who cites it
13 citing papers in PubMed.
- Article
- Wild jackdaws recognise the contact calls of their mate.Animal cognition · 2025Article
- The fish challenge to vertebrate cognitive evolution.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Review
- Why did the human brain size evolve? A way forward.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Article
- Linking individual fitness to the evolution of cognition.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Review
- Evolution of cellular architecture and function of the hippocampus: insights from the artificial selection experiment.Biology letters · 2025Article
- Pair-bond strength is consistent and related to partner responsiveness in a wild corvid.Proceedings. Biological sciences · 2025Article
- Extending the social cohesion hypothesis: is group social structure associated with dispersal in yellow-bellied marmots (Current zoology · 2024Article
- Brain energy metabolism as an underlying basis of slow and fast cognitive phenotypes in honeybees.The Journal of experimental biology · 2024Article
- Evolutionary-developmental (evo-devo) dynamics of hominin brain size.Nature human behaviour · 2024Article
- Short-term memory, attentional control and brain size in primates.Royal Society open science · 2024Article
- Phylogenetic comparative analysis of the cerebello-cerebral system in 34 species highlights primate-general expansion of cerebellar crura I-II.Communications biology · 2023Article
- The selfish preen: absence of allopreening in Palaeognathae and its socio-cognitive implications.Animal cognition · 2023Article
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3 authors.
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Abstract
There are multiple hypotheses for the evolution of cognition. The most prominent hypotheses are the Social Intelligence Hypothesis (SIH) and the Ecological Intelligence Hypothesis (EIH), which are often pitted against one another. These hypotheses tend to be tested using broad-scale comparative studies of brain size, where brain size is used as a proxy of cognitive ability, and various social and/or ecological variables are included as predictors. Here, we test how robust conclusions drawn from such analyses may be. First, we investigate variation in brain and body size measurements across >1000 bird species. We demonstrate that there is substantial variation in brain and body size estimates across datasets, indicating that conclusions drawn from comparative brain size models are likely to differ depending on the source of the data. Following this, we subset our data to the Corvides infraorder and interrogate how modelling decisions impact results. We show that model results change substantially depending on variable inclusion, source and classification. Indeed, we could have drawn multiple contradictory conclusions about the principal drivers of brain size evolution. These results reflect concerns from a growing number of researchers that conclusions drawn from comparative brain size studies may not be robust. We suggest that to interrogate hypotheses of cognitive evolution, a fruitful way forward is to focus on testing cognitive performance within and between closely related taxa, with an emphasis on understanding the relationship between informational uncertainty and cognitive evolution.
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