Crocodiles are neither mammals nor amphibians; they are classified as reptiles. Reptiles are a separate category of animals that also includes snakes, lizards, and turtles. Unlike mammals, reptiles do not have fur or mammary glands and typically lay eggs. They have scaly skin that helps protect them from the environment and retain moisture.
While amphibians, such as frogs and salamanders, typically require a moist environment and often go through a metamorphosis from water to land, crocodiles are more suited to life in a variety of habitats, including freshwater and brackish waters. They breathe air through lungs, like mammals do, but their biological and anatomical features align more closely with reptiles.
In summary, while crocodiles share some characteristics with both mammals and amphibians, they are uniquely classified as reptiles, showcasing distinct features that set them apart from these other animal groups.