Animal: Amphibian

Main types: Caecilian, Frog, Salamander and Toad

Animal Type: Amphibian

Habitats: Desert (Frog/Toad), Island (Frog/Salamander/Toad), Prairie and Steepe (Frog/Salamander/Toad), Savanna (Frog/Toad), Scrubland (Frog/Salamander/Toad), Temperate Forest (Frog/Salamander/Toad), Tropical Rain Forest (All) and Wetland, River and Lakes (All)

The Amphibian:

An amphibian is a cold-blooded four-legged vertebrate (having a back bone) that lives part of its life in the water. There are three main groups of amphibians, those having a tail, frogs, toads and others that do not have a tail and amphibians that have no limbs at all.

Amphibians are similar to reptiles in some ways, but they are actually quite different animals. One such difference is the unique ability for amphibians to breathe through their skin. While intriguing, this makes them much more sensitive to changes in their surrrounding environment.

Frogs and Toads

Frogs and toads are the most recognizable type of amphibians. They vary in size and coloration and some excrete poisons through their skin that are a great defense against predators. Poisonous frogs tend to advertise their toxicity with bright colors .Frogs are known to have long back legs giving them good jumping ability and long tongues to catch insects. Toads on the other hand tend to be larger and less mobile than frogs. They breathe air despite living in and around water.

The loud "ribbit" sound in the night is another unique frog characteristic. Some frog calls are so loud, they can be heard up to a mile away. The call of a frog is unique to each species. Frogs call by passing air through the larynx in the throat. In most calling frogs, the sound is amplified by one or more vocal sacs, membranes of skin under the throat or on the corner of the mouth that expands during the call.

The greatest diversity of frogs occurs in the tropical areas of the world, where water is readily available, suiting frogs' requirements due to their skin. Some frogs inhabit arid areas such as deserts, where water may not be easily accessible. Consisting of more than 5,000 species described, they are among the most diverse groups of vertebrates.

Salamanders

Salamanders are the most common type of tailed amphibian. Most are small, but some reach up to 5 inches (130 mm) in length. The largest salamanders can be a foot (30cm) or more. They also vary in size and coloration. The moist skin of these amphibians usually makes them reliant on habitats in or near water or under some protection on moist ground, often in a swamp. They lay shelless eggs in water. They are capable of regenerating lost limbs. Despite their physical similarities, salamanders are no more closely related to lizards than they are to mammals. They also breath air.

Species of salamanders are numerous and found in most moist or arid habitats in the northern hemisphere. They live in brooks and ponds and other moist locations such as under rocks.

Caecilians

The least well-known group of amphibians are caecilians, or limbless amphibians. Thye live primarily underground and in the water. The smaller species resemble worms, while the larger species with lengths up to 1.5 m resemble snakes. Their skin is smooth and usually dark and they have scales under the skin. Some even have poisonious skin like some frogs. Owing to their underground life the eyes are small and covered by skin for protection, which have led to the misconception that they are blind. Their vision is however limited by the skin covering their eyes. All Caecilians have lungs, but also use the skin or the mouth for oxygen absorption.

Food Chain

Amphibians feed on many types of insects and inverterbrates, including earthworms, snails and spiders. Larger amphibians tend to eat larger prey. Many frogs are quite small (less than 1 in (25 mm) in head-body length) and thus eat only small insects and spiders. Larger-mouthed frogs also tend to eat larger animals, which may include other frogs, lizards and small snakes, birds, and mammals.