Amphibians

Amphibians (class Amphibia), such as frogs and toads, are cold-blooded animals that metamorphose from a juvenile water-breathing form, to an adult air-breathing form. Though amphibians typically have four limbs. Unlike other land animals, amphibians lay eggs in water. Amphibians are superficially similar to reptiles.

Amphibians are ecological indicators, and in recent decades there has been a dramatic decline in amphibian populations around the globe. Many species are now threatened or extinct.

Malaysia has more than 165 species of frogs and toads, which live mainly in the rainforest and in wetland areas. There are a number of endemic species, some unique to Peninsular Malaysia, others to Sabah and Sarawak. Among the unusual frogs in Malaysia are three species of tree frogs which can 'parachute' from the tree canopy to the forest floor, and another species whose eggs develop directly into froglets.

Characteristics

Reproduction

For the purpose of reproduction most amphibians require fresh water. Almost all of these frogs live in wet tropical rainforests and their eggs hatch directly into miniature versions of the adult, passing through the tadpole stage within the egg. Several species have also adapted to arid and semi-arid environments, but most of them still need water to lay their eggs. Symbiosis with single celled algae that lives in the jelly-like layer of the eggs has evolved several times. The tadpoles breathe with exterior gills. After hatching, they start to transform gradually into the adult's appearance. This process is called metamorphosis. Typically, the animals then leave the water and become terrestrial adults, but there are many interesting exceptions to this general way of reproduction.

The most obvious part of the amphibian metamorphosis is the formation of four legs in order to support the body on land. But there are several other changes:

• The gills are replaced by other respiratory organs, i.e., lungs.

• The skin changes and develops glands to avoid dehydration.

• The eyes develop eyelids and adapt to vision outside the water.

• An eardrum is developed to lock the middle ear.

• In frogs and toads, the tail disappears.

Amphibia Metamorphosis

Life Cycle of A Frog or Toad

Information here includes

• • Frog and toads

  • Malaysian species

  • Habitat

• Defense

  • Large and small

  • Poisonous toads

  • Frog wars

• Conservation

Here are some pictures of the amphibians in Malaysia.

More links about amphibian:

1. http://en.wikipedia.org/wiki/Amphibians