ArticleProceedings. Biological sciences2016
The costs of a big brain: extreme encephalization results in higher energetic demand and reduced hypoxia tolerance in weakly electric African fishes.
Article in Proceedings. Biological sciences, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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Who cites it
16 citing papers in PubMed, 56 citations in OpenAlex.
- Specialization of male reproductive tactics corresponds with large gonads and small brains.Evolution; international journal of organic evolution · 2026Article
- The fish challenge to vertebrate cognitive evolution.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Review
- Beyond the mosaic model of brain evolution: Rearing environment defines local and global plasticity.Annals of the New York Academy of Sciences · 2024Article
- Environmental complexity and regularity shape the evolution of cognition.Proceedings. Biological sciences · 2024Article
- Evolution of neural circuitry and cognition.Biology letters · 2024Review
- Oxygen and the Spark of Human Brain Evolution: Complex Interactions of Metabolism and Cortical Expansion across Development and Evolution.The Neuroscientist : a review journal bringing neurobiology, neurology and psychiatry · 2024Article
- How hibernation in frogs drives brain and reproductive evolution in opposite directions.eLife · 2023Article
- Article
- Convergence is Only Skin Deep: Craniofacial Evolution in Electric Fishes from South America and Africa (Apteronotidae and Mormyridae).Integrative organismal biology (Oxford, England) · 2022Article
- Hypoxia Tolerant Species: The Wisdom of Nature Translated into Targets for Stroke Therapy.International journal of molecular sciences · 2021Review
- Neuromodulation or energy failure? Metabolic limitations silence network output in the hypoxic amphibian brainstem.American journal of physiology. Regulatory, integrative and comparative physiology · 2021Article
- Oxygen, evolution and redox signalling in the human brain; quantum in the quotidian.The Journal of physiology · 2019Review
- Testing ontogenetic patterns of sexual size dimorphism against expectations of the expensive tissue hypothesis, an intraspecific example using oyster toadfish (Ecology and evolution · 2018Article
- RETRACTED ARTICLE: The quantum physiology of oxygen; from electrons to the evolution of redox signaling in the human brain.Bioelectronic medicine · 2018Review
- Why are there so many explanations for primate brain evolution?Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2017Review
- The costs of a big brain: extreme encephalization results in higher energetic demand and reduced hypoxia tolerance in weakly electric African fishes.Proceedings. Biological sciences · 2016Article
Corrections and comments
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Authors and funding
4 authors at 1 institution in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
A large brain can offer several cognitive advantages. However, brain tissue has an especially high metabolic rate. Thus, evolving an enlarged brain requires either a decrease in other energetic requirements, or an increase in overall energy consumption. Previous studies have found conflicting evidence for these hypotheses, leaving the metabolic costs and constraints in the evolution of increased encephalization unclear. Mormyrid electric fishes have extreme encephalization comparable to that of primates. Here, we show that brain size varies widely among mormyrid species, and that there is little evidence for a trade-off with organ size, but instead a correlation between brain size and resting oxygen consumption rate. Additionally, we show that increased brain size correlates with decreased hypoxia tolerance. Our data thus provide a non-mammalian example of extreme encephalization that is accommodated by an increase in overall energy consumption. Previous studies have found energetic trade-offs with variation in brain size in taxa that have not experienced extreme encephalization comparable with that of primates and mormyrids. Therefore, we suggest that energetic trade-offs can only explain the evolution of moderate increases in brain size, and that the energetic requirements of extreme encephalization may necessitate increased overall energy investment.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.