We humans aren’t the only creatures with lungs.
All mammals have them, from the tiny bumblebee bat, the smallest mammal, to the great blue whale, the largest. So do spiders, lizards, frogs, and many other creatures. But no lungs can compare to birds’ lungs for efficiency and flow.
Human lungs fill and empty like balloons, but birds’ lungs are different. They work as part of a circuit that gives birds a constant air supply. It’s no wonder birds can soar to the top of Mount Everest, where the air is thin. Most humans need tanks of oxygen to hike there.
