“…Although we do not know the thermoregulatory consequences of variations in rete anatomy, if the rete is important in balancing fluid and temperature regulation, those species without a rete may well be disadvantaged in the face of climate change. Indeed, possession of a rete has been advanced as one factor contributing to the proliferation of artiodactyl species, relative to perissodactyl species (in which the rete is absent), over evolutionary time (58). Although, as perissodactyls, equids do not have a carotid rete, Nature published a report that exercising horses use SBC (7), despite the authors of the study not having measured brain temperature; when we made the necessary measurements, we found no evidence for SBC in freeliving horses (57).…”