A virtual model of the skull of Euoplocephalus tutus, a tanklike ankylosaurid dinosaur from the Late Cretaceous. Air flowing through this dinosaur's convoluted nose would cool the blood headed to the brain. (Witmer Lab)
Carrying around an exoskeleton of bony armor is hard work. But armored ankylosaurs figured out a way to shoulder the load and stay cool. These Cretaceous dinosaurs had "Krazy Straw" nasal passages that helped them air-condition their brains, according to a new study.