Hotter is Smarter: The temperature-dependence of brain size in vertebrates
- Published
- Accepted
- Subject Areas
- Animal Behavior, Ecology, Evolutionary Studies, Zoology
- Keywords
- encephalization, allometry, metabolic rate, cranial capacity, metabolic theory
- Copyright
- © 2013 Gillooly
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
- Cite this article
- 2013. Hotter is Smarter: The temperature-dependence of brain size in vertebrates. PeerJ PrePrints 1:e155v1 https://doi.org/10.7287/peerj.preprints.155v1
Abstract
The tremendous variation in brain size among vertebrates has long been thought to be related to differences in species’ metabolic rates. Species with higher metabolic rates can supply more energy to support the relatively high cost of brain tissue. And yet, while body temperature is known to be a major determinant of metabolic rate, the possible effects of temperature on brain size have scarcely been explored. Thus, here I explore the effects of temperature on brain size among diverse vertebrates (fishes,amphibians, reptiles, birds and mammals). I find that, after controlling for body size,brain size increases exponentially with temperature in much the same way asmetabolic rate. These results suggest that temperature-dependent changes inaerobic capacity, which have long been known to affect physical performance, similarly affect brain size. The observed temperature-dependence of brain size may explain observed gradients in brain size among both ectotherms and endotherms across broad spatial and temporal scales.
Supplemental Information
Appendix 1: Data and sources used in analyses.
Appendix 1: Data and sources used to analyze effects of body mass (g) and temperature ( o C) on relative brain mass (% body mass) in vertebrates.