There are some strange creatures out there, both in the past and the present. One of those oddities is the Ankylosaur, who was a hugely armored beast. Bone structures protruded out of his back, spine, flanks, tail and head, giving the massive beast an advantage against predators.
However all that bone made heating and cooling of the brain a challenging task. The beast's evolution answered this with a made hatter approach to nasal passages, with all manner of twisted passage ways in its brain pan, regulating air temperature.
It seems it would make a head cold a bloody nightmare.