What is "amphibian"?

Amphibian refers to a group of cold-blooded vertebrates that spend part of their lives in water and part on land. They are characterized by their ability to absorb oxygen through their skin and are also known for their unique life cycle which includes a larval stage with gills and a metamorphosis to an adult stage with lungs. Amphibians include frogs, toads, salamanders, and newts, and are found all over the world except for Antarctica. They are an important part of many ecosystems, serving as both predators and prey, and their sensitive skin makes them useful for monitoring environmental changes. However, many species of amphibians are facing threats such as habitat destruction, pollution, and disease, and are in danger of extinction.