Salamanders and newts have elongated bodies with long tails and at first glance, resemble lizards. However, the salamander does not have scales, external ear openings or clawed digits on their feet. Most have two pairs of legs, but some species have lost on pair, usually the hind legs. The front legs never have more than four digits on each foot, or five on each hind foot. Many aquatic species have webbing between the digits on the hind feet that aid in swimming.
The body of the salamander is covered with naked, flexible skin which requires water or constant high humidity during the entire life cycle. Therefore, salamanders are found living in damp and wet environments. The skin is shed quite frequently, either as a whole skin or in small pieces and is often consumed by the animal.
Salamanders and newts have true teeth in both jaws. These animals are carnivores and live on such invertebrates as insects, slugs, snails or worms. They may also practice cannibalism. In turn, the salamander is preyed upon by shrews, birds, snakes, beetles, centipedes and spiders. They rely on several defense techniques for protection from predators which include cryptic coloration, nocturnal movements, a breakable tail, and the ability to excrete a foul smelling substance. Their skin glands give off poisonous secretions that can kill small predators. If the substance is rubbed into human eyes, it causes a searing pain.
Most salamanders and newts spend some part of their lives in fresh water, and most undergo a metamorphosis when they lose their gills and become terrestrial animals. They inhabit many habitats including aquatic, terrestrial or amphibious. The aquatic species are found in fresh water settings, and some never leave the water. Terrestrial species might be found living under rocks or decaying ground litter while others burrow deep into the ground. Some species are arboreal and live quite a distance up into trees. Salamanders are most often found in temperate regions. Very few species have been found in the tropical regions of Central and South America.
During dry weather, salamanders burrow into subterranean areas in search of moisture and food. During freezing conditions, they survive by burying themselves in the ground, muddy water or hide beneath rocks and enter a state of torpor (sluggishness or inactivity). Basically these creatures are secretive, solitary and nocturnal. However it is not unusual for them to come out on a rainy day. Though loners, they will hibernate together or mass together for the purpose of migration.
Not much is knows about the breeding habits of salamanders and newts. The eggs they lay are not covered by shells, but have a thick gelatin-like substance for protection. Depending on the habitat, there are at least three typical life cycles. Terrestrial species breed on land and lay their 20-30 eggs on land. The larval stage takes place within the egg and when hatched miniature adults emerge. Aquativ species breed in water. As many as 500 eggs hatch into larvae. Some of the larvae features are retained ad they grow into adulthood. The amphibious species begin life in water as larvae. Most spend part of their adult life on land. When ready to reproduce, they migrate to water to breed then reenter the water for their rest of their life. Salamanders are capable of living a long time, one captured specimen lived for 52 years.