How do the foods of frogs and tadpoles compare?
Class characteristics: Smooth, moist skin (no scales) Toes lack claws Gills, lungs, and skin used in respiration Metamorphosis from aquatic larval stage to adult form Larvae heart 2-chambered, adult heart 3-chambered Eggs fertilized externally There are three orders of living amphibians containing about 170 genera. The majority of amphibians are found in tropical regions with abundant rainfall. Correlated with the moisture requirement of amphibians is the fact that most forms are nocturnal. The class name means “two lives”, indicating that amphibians are able to survive both in water and on land. They represent an important step in the phylogeny of vertebrates, the bridge from water onto land. No amphibians live in the ocean, but some will tolerate brackish water. Amphibian lungs are poorly efficient. For this reason, most amphibians also use their moist skin for respiration. Temperature is another key factor in the life of amphibians. Being ectothermic, their body temperature changes
