What physiological process do narwhals utilize to conserve oxygen during extreme deep dives?

Answer

Bradycardia (slowing heart rate)

To manage pressure changes during deep descents and ascents, narwhals slow their heart rate significantly, a process known as bradycardia, in addition to collapsing their lungs.

What physiological process do narwhals utilize to conserve oxygen during extreme deep dives?
animalTuskNarwhal