Amphibians and water are tied very closely together. Many of the species live in water, near water, or lay their eggs in or near water. With that said, there are a few species that have adapted to survive in cold and drought conditions. The skin of the amphibian is smooth and naked. It has no scales or hair to protect it. The skin is also permeable to water. Even though many have glands that secrete mucous, they will dry out quickly if they are not able to find a moist place. All amphibians have poison glands in their skin and many have secretions that are distasteful or highly toxic to potential predators.
There are three stages of amphibian development. For most of the amphibians, the female will lay eggs in water. The male will fertilize the eggs (stage 1). In a about a week, the eggs will hatch (Stage 2) into tadpoles with a spherical body and a well developed tail. The tadpoles have well developed gills. In four weeks, or so, these gills have been absorbed and replaced with internal gills. Between six and nine weeks, the back limbs start to develop, the head becomes for streamlined. The gills are replaced by lungs and the legs become more functional. After nine weeks, the front legs have emerged. The tail will gradually be absorbed into the body. (Stage 3) The frog will move out of the water and start the cycle all over again.
Amphibians are separated into three categories: 1) Newts & Salamanders; 2) Caecilians; and 3) Frogs & Toads. At Scovill Zoo we have amphibians representing two of those categories. We have Salamanders, Frogs, & Toads.