Why are amphibians very colourful?

Amphibians can be red, blue, yellow, brown, or green and they come with spots, stripes, and many different types of markings. Some are darker on top with a completely different colour and pattern underneath. An amphibian's colour may vary with humidity too, becoming pale when warm and dry, and dark when cold and damp.

There are several reasons why amphibians come in different colours. A bright colour is used to tell other animals whether a particular animal is poisonous or not. Tropical colours like reds, oranges and blues are so bright that they can be seen from afar. These colours signal predators that the animal is poisonous, and shouldn't be eaten. On the other hand, some amphibians have bright colours to scare their enemies away. Many can change their colouring to mimic their surroundings, so that their enemies can't see them. 


Why is the respiratory system of amphibians different?

Amphibians live on both land and water, and so, their respiratory system must allow them to take in oxygen not only from the air, but also from water. Thus, they have a very complex respiratory system.

            When amphibians stay in the water, they breathe through their skin, but once they come on land, they breathe with their lungs, and through the membranes in their mouth. Even when the lungs are used, amphibians obtain oxygen through their skin- and for this to be possible, the skin must remain moist at all times.



            When an amphibian is in the larval stage, it uses gills for breathing. These gills later develop into lungs as the amphibian undergoes the changes that make it an adult. Some salamanders have neither gills nor lungs, but breathe through their mouths and skins.



            To sum up, amphibians can get oxygen into their bodies in three different ways. The first way is by using lungs, which are similar to ours. The second way is through their skin, and the last way, is by using gills. Did you know that amphibians don’t breathe constantly like humans do? Instead, they just breathe now and then, when their body needs more oxygen.



 


Why is water important to amphibians?

 For amphibians, water is essential for survival. To begin with, water keeps their skin moist, and they get the oxygen they need from the water that they absorb through their skin. Water is also vital for their reproduction. This is because the eggs of amphibians do not have a hard shell so they need water to keep them from drying out, and to protect them from the rays of the sun. Some species of amphibians are aquatic, and spend all their lives in water. Others spend the beginning of their lives in water as larvae, and later undergo a change called metamorphosis, and move on to land.

            Since, water is so important to them, amphibians like frogs seek out damp shady places to live in. Others try to prevent water loss by burrowing underground. In spite of being so dependent on water, amphibians rarely drink it! Isn’t that strange?


Why is it said that amphibians are found worldwide?

Amphibians are found all over the world, except in Antarctica and Greenland. They are found both on land, and in fresh water. Frogs are the common amphibians. You can find frogs in water, or near places that have water, like ponds and streams. However, some frogs will never enter the water. They live mainly on land. Then, there are some kinds that live in trees. Some frogs are burrowers. Frogs that live in cold places, hibernate during winter time.

            Salamanders are found in North, South and Central America, Europe and Asia, and some species are found in Africa too.



            Caecilians are found in swampy places in most tropical parts of the world.


Why are the skeletons of amphibians interesting?

 Amphibian’s skeletons are made of bones. They have fewer bones than their fishy ancestors, and over the years, the evolutionary changes in the amphibian family have gone in two directions. The frog family has a broad head, large eye sockets, short spine, no tail, and long hind legs. The caecilian group has skeletons with small tubular skulls, tiny eye sockets, long spines, and no legs at all.



 The skeletons of salamanders and newts are adapted for a primitive form of walking. A frog’s skeleton, on the other hand, is specially adapted for leaping and swimming. The backbone is the base of an amphibian’s skeleton, and is made of vertebrae. Ribs still remain underdeveloped. By comparing the skeleton of modern amphibians with the fossils of ancient ones, it is possible to determine the era in which they lived.



 


Why are sirens special?

 Sirens are probably the most ancient line of salamanders now alive on planet Earth. They are large eel like creatures that can reach 40 centimetres in length and are 2.5 centimetres in diameter. They have a pair of small front legs that they use to pull themselves along through the muddy murky world of the swamps that they live in. They have no hind legs.

            Sirens are special, because they can breathe through their lungs and skin, and also through feathery gills. Unlike other salamanders, each of their four toes ends in a claw or toenail. They also have small horny beaks in their mouths instead of teeth – and their teeth are located in their throats! They don’t bite, and aren’t poisonous – and are very, very shy indeed!


Why is the early history of amphibians fascinating?

  Amphibians evolved from fish about 400 million years ago, when the amount of dry land on Earth increased greatly. Certain fish adapted to these changing conditions by developing limbs to crawl with, and lungs to breathe. They came to be called ‘amphibians’, and were the first animals with backbones to live on land. The largest variety of amphibians lived around 360 million to 230 million years ago, when the climate was constantly alternating between wet and dry.

            The first amphibians were Temnospondyls. They were long-headed amphibians with a sprawling gait and distinctive look. The early Temnospondyls were the size of large fish. They had stubby feet, and probably couldn’t move very fast. Temnospondyls grew in size and diversity until some even grew as large as crocodiles. This animal, Prionosuchus is the largest amphibian known. Lissamphibians, the group that includes all modern amphibians and their common ancestors, emerged about 300 million years ago.


What do we know about the origin of amphibians?

  Amphibians first appeared on Earth around 360 million years ago. For tens of millions of years, they were the dominant land animals on Earth. Some of these ancient creatures were very big, and they terrorized smaller animals. Amphibians evolved from fishes that had fins that looked like legs. These fish may have crawled on to the land to escape their enemies, and also because they were attracted by the good supply of food on land.

            Gradually, these first amphibians developed lungs for breathing, and their fins developed into limbs for crawling. Over hundreds of millions of years, many different amphibians evolved and disappeared, leaving the familiar salamanders and frog of today.


What are amphibians?

The word amphibian means double life-and amphibians are animals that are called by this name, because they need both land and water during their life cycle. They start life in the water, and wind up on land as adults. Amphibians are vertebrates, which mean that they have a backbone, and they are also cold blooded. Do you know what a cold blooded animal is? It is an animal that cannot regulate its own body heat. So, an amphibian depends on its surroundings for warmth, and its body temperature varies according to the surroundings.



Another interesting feature of amphibians is that they have no hair, feathers, or surface scales. They can breathe through their skin, though some amphibians have lings as well. Frogs and toads are some of the most common amphibians, which mean that all of us have seen an amphibian at some time or the other.