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  • Review Article
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Numerical cognition in birds

Nature Reviews Psychology volume 4, pages 576–590 (2025)Cite this article

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Abstract

Avian species are one of the most diverse and adaptable groups of animals: there are far more species of birds than of mammals, and they occupy a broad range of habitats. Birds and mammals split from a common ancestor over 300 million years ago. Yet certain bird species can perform complex mental tasks, including numerical problems, at levels similar to — and in some cases surpassing — primates, including great apes. Birds thus offer a privileged perspective on the cognitive functions underlying numerical abilities and their evolution. Moreover, birds provide excellent models for studying the ontogenetic development and neural mechanisms underlying numerical computations. In this Review, we provide a comprehensive picture of the contribution of avian studies to understanding numerical cognition, including behavioural laboratory studies, field studies and neurobiological investigations. We also critically examine the methodologies, interpretations and limitations of selected key studies. By synthesizing current knowledge and situating it within the broader field of cognitive research, we highlight the importance of a comparative perspective in understanding the role of evolutionary convergence in the emergence of cognitive functions.

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Fig. 1: Experimental paradigms to study avian numerical cognition under controlled conditions.
Fig. 2: The phylogenetic relationship between avian orders.
Fig. 3: Ecological studies of avian numerical cognition.
Fig. 4: Avian and mammalian brains.
Fig. 5: Number cell response tuning curves.

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Acknowledgements

The authors acknowledge support from PRIN (Progetti di Rilevante Interesse Nazionale - Projects of Relevant National Interest) 2022 PNRR (Piano Nazionale di Ripresa e Resilienza - National Plan for Recovery and Resilience) (grant P2022TKY7B to L.R. and R.R.) and PRIN 2022 (grant 202254RHRT to R.R.). This project was supported by funding from the European Research Council under the European Union’s Horizon 2020 Research and Innovation programme (grant 833504 SPANUMBRA). M.L. was funded by the European Union (NextGenerationEU) and by the University of Padua under the 2023 STARS Grants@Unipd programme (project CROSS).

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Authors and Affiliations

  1. Department of General Psychology, University of Padua, Padova, Italy

    L. Regolin, M. Loconsole, K. Brosche, M. Macchinizzi, A. Felisatti & R. Rugani

  2. Centre for Mind/Brain Science, University of Trento, Rovereto, Italy

    O. Rosa-Salva

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  1. L. Regolin
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  2. M. Loconsole
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  5. M. Macchinizzi
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  7. R. Rugani
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Contributions

L.R., M.L., O.R.-S. and R.R. conceptualized the review. L.R., M.L., O.R.-S., K.B., M.M., A.F. and R.R. performed the literature search. O.R.-S., K.B., M.M. and R.R. created drafts of the figures. L.R., M.L., O.R.-S. and R.R. wrote the initial draft of the manuscript. All authors critically reviewed the manuscript and approved its final version.

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Correspondence to L. Regolin.

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Regolin, L., Loconsole, M., Rosa-Salva, O. et al. Numerical cognition in birds. Nat Rev Psychol 4, 576–590 (2025). https://doi.org/10.1038/s44159-025-00480-8

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