Avians:

Supreme flyers

-Unique among all other animals due to their feathers, birds are one of the most fascinating creatures in the Animal Kingdom. They are such unusual creatures that scientists are finding it difficult to exactly say from which other creatures they might have evolved from. It is basically presumed that birds first appeared during the time of dinosaurs. Going by fossils of a primitive bird found in a quarry in Germany, scientists say that birds lived about 150 million years ago.

The fossils of the primitive bird which the scientist named Archaeopteryx have revealed that the early birds not only had feathers and the usual bones of modern day birds, but also reptile like teeth, a bony tail and claws along its wings. Some scientists are of the view that birds evolved from reptiles due to the teeth formation and bony tail of the Archaeoptevyx.

Many others say the present day birds are flying dinosaurs, because they believe that some of the smaller species of dinosaurs such as the Compsognathus developed their long feathery scales over the years enabling them to fly. But how could scales develop into feathers, you may wonder. The main reason for this view is that scales and feathers are made from keratin, which is also the substance that forms our hair and finger nails. Many fossil expert say that these scales could have easily evolved into feathers by developing the shaft and filaments that make up the feathers of present day birds.

No matter how or when birds originated, no one can dispute the fact that they are a wonderful species of animals that add colour and beauty to our world.

Our feathered friends in the avian world are indeed nature's supreme flyers and their aerial skills cannot be easily duplicated by man.

Birds come in a variety of sizes, with the smallest, the bee hummingbird weighing no more than a coin, to the largest the gigantic ostrich which is taller and heavier than even an adult human.

There are over 8600 different kinds of birds distributed throughout the world from one end of the pole to the other. Just as varied the birds are, are their lifestyles and habitats.

There is basically no place on Earth that birds are not found. They live in all kinds of habitats from extreme deserts to freezing pack-ice zones, on land or in water and from sea level to high mountains. Each species may display different traits in behaviour and physical appearance, but in general all birds have many common features; they all have feathers, beaks, wings and two clawed feet. They also lay eggs and hatch them. Of cause when it comes to hatching, just like flying, their are exceptions to the rule. Some lazy birds do not ``hatch' their eggs by sitting on them as is the common practice with most birds. They use the heat of volcanic activity, the sun and even rotting vegetation to hatch their eggs. There are some species of bird which take the easy way out and lay their eggs in another birds's nest. An ideal way to save energy, don't you think? And when it comes to flying, even though we normally associate flying with birds, not all birds have the ability to fly. Flight becomes virtually impossible for birds weighing over 15 kg. There are some species who are bordering on the heavy weight limit who manage to fly, such as the Kori bustard.

It is a turkey-like bird from Europe and Asia which is classed as the heaviest flyer as it weighs around 12-15 kg. The other is a swan.

Do you know that the swan needs a running start from the surface of a lake to reach a sufficient speed for take off, because it is so heavy?

Having the ability to fly is so fascinating and birds are indeed fortunate to be attributed with this skill, naturally. We humans can only do so with the assistance of artificial equipment such as parachutes, gas balloons and so on. But why do birds fly when other animals don't? They do so mostly to find food that other animals cannot reach and also to escape from ground based predators and extreme weather conditions

You would be amazed to learn that some birds such as the wandering albatross can forage for food over a huge area in a very short period of time without even landing. It hunts for its food while still flying or 'on the wing' as it's generally called.

Birds are fascinating creatures we can never tire of learning about because there are millions inhabiting the planet. Bird experts believe that there are over 300 billion birds alive in the world today. That is roughly about 50 birds for every person on the planet. So, find out more about these feathered beauties.

Fast facts:

* About 8,500 - 10,000 species of birds survive today in the world.

* Animals with large complex brains such as mammals and birds are believed to have the ability to learn and adapt to new conditions.

* An ostrich, striding the plains of central and southern Africa can grow to a height of 2.74m and weigh 160 kg. However, though it is the largest living bird today it is not the largest bird that ever lived. Dromarnis stirtoni, a flightless bird like the ostrich thrived in Australia about 15 million years ago. It reached three metres in height and weighed up to 500 kg.

* A typical bird's feathers are coloured from pigments produced by the bird itself in its skin or from something it has eaten.

* Feathers weigh about two to three times as much as the bird's skeleton and account for five to seven per cent of total bodyweight.

* Bills or beaks of birds come in a huge range of shapes, sizes and colours. They are the main implements a bird uses to catch and eat its food. It is also vital for preening the feathers to keep them in working order.

* Some birds such as woodpeckers have specialised beaks they use as a tool like a chisel or drill to bore holes.

* The toco toucan has a huge beak that is about 19 cm long.

* The young hoatzin, a bird found in the forests of Brazil is said to have 'four-feet' because it has claws on its wings. The chick uses its claws to climb back up to a tree when it falls out of its nest. The claws are shed before adulthood.

* The peregrine falcon is the fastest flying bird. It has been estimated to reach speeds up to 320 km/h as it stoops out of the sky to attack prey.

* Different species of bird have different wing beats. Herons are among those with the slowest wing beats. They flap their wings at a lazy two or three times a second while most birds beat their wings at between three and eight times a seconds.

* Hummingbirds must reach rates of 78 beats per second in order to hover. The wings appear as a blur then.