How to Compare Reptiles & Amphibians

Because of their similar lifestyles and secretive habits, reptiles and amphibians are often grouped together. Actually, these two distinct groups are only distantly related. If you know what to look for, you can quickly and easily tell them apart.

  1. Different Skin

    • The quickest way to compare reptiles and amphibians is to look at the animal's skin. Reptiles like snakes and lizards are covered in hundreds or thousands of small, hard scales. Amphibians like frogs and salamanders have smooth, moist skin.

    Life Cycle

    • While amphibians and reptiles may lead similar lives as adults, they develop in very different ways. Most amphibian eggs are laid underwater and hatch into a larva, called a tadpole or pollywog. This larva lives underwater, breathing through gills like a fish, until it transforms into an adult frog or salamander. Reptile eggs are laid on land, and the newborns look like tiny versions of the adults.

    Breeding Biology

    • Reptiles and amphibians also differ in the way they mate. Amphibians utilize external fertilization, meaning that the female lays the unfertilized eggs and the male deposits his sperm directly on them. Reptiles use internal fertilization, just like humans. In this process the male and female mate, and the eggs and sperm meet inside the body of the female.

    Ectothermic

    • One characteristic that reptiles and amphibians share is that they are both ectothermic, or cold-blooded. This means that they are unable to regulate their own body temperatures and must use their environment to do so. For example, they may bask in the sun to warm up or become active, or rest in the shade to cool down or rest.