In a new study, paleontologist revealed that Armour–plated dinosaur had an exceptional capability to change the temperature of the air they breathed with the help of their long, winding nasal passages as heat transfer devices. The ultimate goal of the technique was to keep their brain from overheating. Other animal species follow several other measure including hiding in shed of a tree, sweating, panting, etc to cool down their brain, but none had the capability to change the temperature of air they took in.
For the research, a team of paleontologist led by Jason Bourke, at Ohio University used CT scans to observe the anatomy of nasal passages in two different ankylosaur species followed by the modelling of airflow using 3d reconstruction technique.
Researchers observed that the convoluted passages provided a large surface, and more time are for the inhaled air to get heated up by using comparatively warmer body temperature. Resulting in cooler intake of atmospheric air that helped in keeping their brains cool.
Perhaps there are two methods to warm the inhaled air, Armour–plated dinosaur used convoluted passage, and another one is by using conchae, scroll-shaped bones to heat up inhaled air. Modern species uses latter one to heat up the inhaled air.
“There are two ways that animal noses transfer heat while breathing,” said Bourke. “One is to pack a bunch of conchae into the air field, like most mammals and birds do – it is spatially efficient. The other option is to do what lizards and crocodiles do and simply make the nasal airway much longer. Ankylosaurs took the second approach to the extreme,” Bourke added.
“Our team discovered these ‘crazy-straw’ airways several years ago, but only recently have we been able to scientifically test hypotheses on how they functioned,” Lawrence Witmer, who was also involved with the study, said. “By simulating airflow through these noses, we found that these stretched airways were effective heat exchangers. They would have allowed these multi-tonne beasts to keep their multi-ounce brains from overheating,” said Witmer.
Similar to nose of homo sapiens, ankylosaur’s nose might have served multiple purposes including generating sound with the help nose in resonance, allowing it be heard over greater distances.