WHY do frogs puff out their mouths?

Each of the boys probably caught frogs and toads in childhood, and then scared the girls with them? I wasn't the only one, right? Never mind. So, you have probably noticed more than once that when the toad is constantly lowered, it raises the bottom of its mouth, as if it has an inch in its mouth, which inflates and deflates the throat with a pump. If you look closely, you can find that in general all amphibians perform similar movements and the little inch with pomposity, of course, has nothing to do with it. And toads move their jaws back and forth for a reason, and not even out of boredom. They breathe like that and can't do it any other way. Mammals feel good, they have ribs and a diaphragm, with their help they can make the movements necessary for breathing. But what about amphibians, which have neither a diaphragm nor ribs? In order not to die from oxygen starvation, they learned not only to breathe through the skin, but also adapted to the use of the so-called normal, or forced, breathing. Here's how it works: the animal lowers the lower part of its mouth the moment the nostrils open. Air fills the mouth through the nostrils. As soon as the oral cavity is filled with fresh air, rich in oxygen, the nostrils close and the floor of the oral cavity rises. Air has only one way - to the lungs. And vice versa: the nostrils close, the mouth cavity descends again, and the exhaust air from the lungs flows back into the mouth. Now the nostrils open, the larynx closes, and the air is forced out through the nostrils. Actually, everything, with one of the main secrets of the universe, the shell has been torn off. Yes, I know the information is shocking. Sit down for five minutes, or rather lie down, comprehend this revelation! And finally: do not scare anyone with toads. They are too cute.