ArticleCommunications biology2021
Brain size and neuron numbers drive differences in yawn duration across mammals and birds.
Article in Communications biology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.
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Who cites it
14 citing papers in PubMed, 30 citations in OpenAlex.
- Article
- Fetal yawning and mouth openings: Frequency, developmental trends, and association with birth weight.PloS one · 2026Article
- Central administration of C-type natriuretic peptide (CNP) modulates food consumption in broilers: involvement of dopaminergic, melanocortinergic, and neuropeptide Y receptors.Veterinary research communications · 2025Article
- Diving back two hundred million years: yawn contagion in fish.Communications biology · 2025Article
- Yawning in sync: implications for social cohesion in horses.Current zoology · 2025Article
- More than a simple fixed action pattern: Yawning in drills.Primates; journal of primatology · 2024Article
- Hemispheric asymmetries and brain size in mammals.Communications biology · 2023Article
- Yawning and airway physiology: a scoping review and novel hypothesis.Sleep & breathing = Schlaf & Atmung · 2022Article
- No Evidence for Biased Attention Towards Emotional Scenes in Bornean Orangutans (Affective science · 2022Article
- Interspecific Contagious Yawning in Humans.Animals : an open access journal from MDPI · 2022Article
- The evolution of brain neuron numbers in amniotes.Proceedings of the National Academy of Sciences of the United States of America · 2022Article
- Two forms of yawning modulation in three months old infants during the Face to Face Still Face paradigm.PloS one · 2022Article
- Factors affecting yawning frequencies in preterm neonates.PloS one · 2022Article
- First evidence of yawn contagion in a wild monkey species.Scientific reports · 2021Article
Corrections and comments
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Authors and funding
13 authors at 6 institutions in 6 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Recent studies indicate that yawning evolved as a brain cooling mechanism. Given that larger brains have greater thermolytic needs and brain temperature is determined in part by heat production from neuronal activity, it was hypothesized that animals with larger brains and more neurons would yawn longer to produce comparable cooling effects. To test this, we performed the largest study on yawning ever conducted, analyzing 1291 yawns from 101 species (55 mammals; 46 birds). Phylogenetically controlled analyses revealed robust positive correlations between yawn duration and (1) brain mass, (2) total neuron number, and (3) cortical/pallial neuron number in both mammals and birds, which cannot be attributed solely to allometric scaling rules. These relationships were similar across clades, though mammals exhibited considerably longer yawns than birds of comparable brain and body mass. These findings provide further evidence suggesting that yawning is a thermoregulatory adaptation that has been conserved across amniote evolution.
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