Amphibians (class Amphibia), such as frogs, toads, salamanders, newts, and caecilians, are ectothermic (or cold-blooded) animals that metamorphose from a juvenile water-breathing form, to an adult air-breathing form. Though amphibians typically have four limbs, the Caecilians are notable for being limbless. Unlike other land animals (amniotes), amphibians lay eggs in water. Amphibians are superficially similar to reptiles.Amphibians are ecological indicators, and in recent decades there has been a dramatic decline in amphibian populations around the globe. Many species are now threatened or extinct.
The most obvious part of the amphibian metamorphosis is the formation of four legs in order to support the body on land. But there are several other changes:
-The gills are replaced by other respiratory organs, i.e., lungs.
-The skin changes and develops glands to avoid dehydration.
-The eyes develop eyelids and adapt to vision outside the water.
-An eardrum is developed to lock the middle ear.
-In frogs and toads, the tail disappears.
-The gills are replaced by other respiratory organs, i.e., lungs.
-The skin changes and develops glands to avoid dehydration.
-The eyes develop eyelids and adapt to vision outside the water.
-An eardrum is developed to lock the middle ear.
-In frogs and toads, the tail disappears.
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WeiJie
Thanks for sharing what you have read Wei Jie.
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