Can fish breathe air?

The varying rainfall in certain areas has resulted in the evolution of the ability to breathe air in various oxygen-poor freshwater fish.

Lungfish are a species of fish that has one or two rudimentary lungs that allow them to extract oxygen even from air and breathe on the surface.

It is an adaptation they have developed to survive frequent droughts, and the lungfish that are native to Africa in particular, are able to slow down their metabolism and breathe air for very long periods of time.

Some species also possess fleshy fins with many muscles, allowing them some freedom of movement as tetrapods.

Instead of the more efficient ventilated lungs, they possess intermittent lungs, which are unable to expand independently and generate a low-pressure zone. Instead, air is swallowed and pushed towards them from the fish’s mouth.

Curiously, their lungs have evolved from modified swim bladders, similar to how they have evolved in all other animals from amphibians.