Characteristics of an amphibian include being ectothermic, having a dual life stage (aquatic larvae and terrestrial adults), and possessing moist skin that aids in respiration and hydration. Amphibians undergo metamorphosis, transitioning from gilled larvae to air-breathing adults. They generally lay their eggs in water, leading to a life cycle that depends on aquatic environments for reproduction. Examples of amphibians include frogs, toads, and salamanders, which all display these defining traits.