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Cited by 528Primate Behavior and EcologyAnimal Behavior and ReproductionCognitive Abilities and Testing

A critique of comparative studies of brain size

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Healy, Susan D, Rowe, Candy·2007·Proceedings of the Royal Society B: Biological Sciences
DOI 10.1098/rspb.2006.3748PMC PMC1766390
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Abstract

In recent years, there have been over 50 comparative analyses carried out in which social or ecological variables have been used to explain variation in whole brain size, or a part thereof, in a range of vertebrate species. Here, we review this body of work, pointing out that there are a number of substantial problems with some of the assumptions that underpin the hypotheses (e.g. what brain size means), with the data collection and with the ways in which the data are combined in the analyses. These problems are particularly apparent in those analyses in which attempts are made to correlate complex behaviour with parts of the brain that carry out multiple functions. We conclude that now is the time to substantiate these results with data from experimental manipulations.

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Crossref · 10.1098/rspb.2006.3748

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  • Comparative tests of adaptive hypotheses to explain brain size evolution in primates sometimes reach incompatible conclusions, as do those on other mammals or birds.

    “Comparative tests of adaptive hypotheses to explain brain size evolution in primates sometimes reach incompatible conclusions [Wartel et al., 2019], as do those on other mammals or birds [Healy and Rowe, 2007].”

    From A Farewell to the Encephalization Quotient: A New Brain Size Measure for Comparative Primate Cognition (2021) · cites this paper as Healy and Rowe, 2007

  • Since ecology, social life and group size are tightly linked in nature, teasing apart the different factors is difficult.

    “Since ecology, social life and group size are tightly linked in nature, the teasing apart of the different factors is difficult (Dunbar & Shultz, 2017;Healy & Rowe, 2007).”

    From Baboons (Papio anubis) living in larger social groups have bigger brains. (2021) · cites this paper as Healy & Rowe, 2007

  • The lack of cognitive data collected with similar methods across large samples of species precludes meaningful species comparisons that can reveal the major forces shaping cognitive evolution across species, including humans.

    “The lack of cognitive data collected with similar methods across large samples of species precludes meaningful species comparisons that can reveal the major forces shaping cognitive evolution across species, including humans (48,70,89,(93)(94)(95)(96)(97)(98).”

    From The evolution of self-control. (2014) · cites this paper as [89]

  • Analyses of anatomical proxies for cognition (e.g., brain size) rely on the assumption that cognition is a one-dimensional, general-purpose mechanism that varies only quantitatively.

    “Although analyses of anatomical proxies for cognition (e.g., brain size) allow researchers to analyze large comparative datasets, they rely on the assumption that cognition is a one-dimensional, general-purpose mechanism that varies only quantitatively (Healy and Rowe 2007).”

    From How does cognition evolve? Phylogenetic comparative psychology (2012) · cites this paper as Healy and Rowe 2007

  • Comparative studies have not produced a single, unified picture of the relationship between comparative brain measures and behaviours.

    “Empirically, there is a problem with this approach: comparative studies have not produced a single, unified picture of the relationship between such measures and behaviours.”

    From Embodied cognitive evolution and the cerebellum (2012) · cites this paper as [14]

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Research works printed but not linked: 13

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Authors
Healy, S. D., & Rowe, C.
Affiliations
  • University of Edinburgh (GB)
  • Newcastle University (GB)
ORCID
Venue
Proceedings of the Royal Society B: Biological Sciences
Publisher
The Royal Society
Published
2006-12-12
Volume
274
Issue
1609
Pages
453-464
ISSN
  • 0080-4649 (ISSN-L)
  • 0962-8452
  • 1471-2954
DOI
10.1098/rspb.2006.3748
PMC
PMC1766390
OpenAlex
W2107996513
Cited by
528
References
105
Citations by year
2026: 11 · 2025: 23 · 2024: 23 · 2023: 15 · 2022: 26 · 2021: 49 · 2020: 31 · 2019: 35 · 2018: 25 · 2017: 30 · 2016: 43 · 2015: 33 · 2014: 33 · 2013: 33 · 2012: 28
FWCI
1.79
Type
journal article
Language
en
Open access
Licence
royalsociety.org/journals/ethics-policies/data-sharing-mining/ (tdm)
Locations
  • Proceedings of the Royal Society B Biological Sciences (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Newcastle University ePrints (Newcastle Univesity)
Topics
  • Social Sciences › Psychology › Social Psychology › Primate Behavior and Ecology
  • Life Sciences › Agricultural and Biological Sciences › Ecology, Evolution, Behavior and Systematics › Animal Behavior and Reproduction
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Cognitive Abilities and Testing
Keywords
brain size, vertebrates, social behavior, ecological factors, experimental manipulation, data collection problems
MeSH terms
Animals, Behavior, Animal, Brain, Biological Evolution, Organ Size, Social Behavior, Species Specificity, Mating Preference, Animal

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