Hotter is Smarter: The temperature-dependence of brain size in vertebrates

Abstract

View the peer-reviewed version (peerj.com/articles/301), which is the preferred citable publication unless you specifically need to cite this preprint. Hotter is Smarter: The temperature-dependence of brain size in vertebratesThe 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.PeerJ PrePrints | https://peerj.com/preprints/155v1/ | v1

Vascular Patterns in the Heads of Dinosaurs: Evidence for Blood Vessels, Sites of Thermal Exchange, and Their Role in Physiological Thermoregulatory Strategies

“…Thermoregulation is arguably one of the most important physiological processes to occur in the body. Maintaining body temperature within strict limits has direct interactions with metabolism (Tattersall et al, 2006;Gillooly, 2013), and protein conformation and efficiency (Guderley and Seebacher, 2011). Thermoregulation can occur via behavioral mechanisms (Cowles and Bogert, 1944), where the animal shifts body position or shuttles from a sunny area to shade, or via physiological mechanisms that use evaporative mechanisms to cool blood (Crawford et al, 1977;Dzialowski and O'Connor, 1999).…”