Amphibian

Amphibian comes from a Greek word meaning "both lives." Most amphibians hatch as aquatic larvae that breathe with gills, then undergo metamorphosis to become air-breathing adults with lungs and damp skin. Frogs lose their tails, salamanders keep theirs, and worm-like caecilians burrow underground, yet all share thin, permeable skin that must stay moist.

Because their skin absorbs water and oxygen, amphibians are sensitive to pollution and drying. They often live near ponds, streams, or forest floors where humidity stays high. Some species dig burrows or hide under logs to avoid the sun, while others climb trees and use suction-like toe pads to stick to leaves.

Amphibian reproduction usually requires water. Adults lay jelly-coated eggs in ponds or rain-filled tree holes. Tadpoles or larvae hatch and feed on algae, plankton, or small invertebrates. As they grow, legs form, tails shorten, and lungs develop, preparing them for life on land. A few species give birth to live young or guard eggs in unusual places, such as in the mouth or on the back.

Diets change with age. Tadpoles are often herbivores or filter feeders, but adults tend to be carnivores that eat insects, worms, and other small animals. Sticky tongues, quick strikes, and camouflage help them catch prey while avoiding predators.

Amphibians act as ecological indicators: when their numbers decline, it signals trouble in the ecosystem. habitat destruction, fungal diseases like chytrid fungus, climate change, and invasive species threaten many amphibians worldwide. Conservation projects create vernal pools, restore wetlands, and breed endangered frogs in protected facilities before releasing them back into the wild.