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A Comparative Approach for Quantitative Cell Counting Studies in Widely Different Mammalian Brains
Published on: January 16, 2026
Relationship between exercise capacity and brain size in mammals
David A Raichlen1, Adam D Gordon
1School of Anthropology, University of Arizona, Tucson, Arizona, United States of America. raichlen@email.arizona.edu
Plos One
|July 7, 2011
Summary
Exercise capacity, measured by maximum metabolic rate, correlates with larger brain sizes across diverse mammal species. This suggests exercise may drive brain evolution, not just cognitive demands.
Area of Science:
- Evolutionary Biology
- Comparative Neurobiology
- Mammalian Physiology
Background:
- Extensive research links exercise to cognition, neurogenesis, and neuroprotection in mammals.
- Previous studies focused on limited species, neglecting evolutionary links between exercise and neurobiology.
- This study investigates exercise-neurobiology relationships across a broad range of mammalian taxa.
Purpose of the Study:
- To test the hypothesis that exercise and neurobiology are related across evolutionary time.
- To examine the association between exercise and brain size in a wide array of mammals.
Main Methods:
- Examined the correlation between brain size and maximum metabolic rate (MMR) as a proxy for exercise.
- Collected brain size and MMR data from scientific literature.
- Utilized phylogenetic independent contrasts to control for evolutionary relationships.
Main Results:
- A significant positive correlation was found between maximum metabolic rate and brain size across diverse mammalian taxa.
- This association remained significant after controlling for body size and phylogeny.
Conclusions:
- Results propose a novel hypothesis linking mammalian brain size evolution to locomotor behaviors and exercise capacity.
- Suggests that increased exercise capacity, rather than solely cognitive abilities, may have driven brain size evolution in many mammals.
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