Among the six basic group of animals, the group ‘Birds’ belonging to the class “Aves” is the most distinguished one. These warm blooded, egg laying vertebrates are mostly unique in their characteristic of having their body covered with feathers with a pair of wings that makes them the master of heights. These are two legged species with a beak and no teeth. They have respiratory and digestive system that is distinctively designed and adaptable for flying. Penguins and the members of duck family, however, do not fly and are adapted to swim. This group have so many features, each exclusive and unique in its own way and is therefore beyond the scope of this article to mention all. Few of the most interesting facts, however, are as follows.
Birds are divided into 30 groups with about 9,865 species currently alive. Of them, 1,227 species are threatened and are on the verge of extinction. It may interest you to know that the Archaeopteryx lithographica was the earliest known bird havings its origin in the Jurassic period about 150 million years ago. It was an amalgam of avian as well as reptilian characteristics and over the years, archeologists have managed to unearth 10 Archaeopteryx fossils.
What makes you distinguish birds from other animals is clearly their feathers. But apart from helping them fly, there are several other equally important functions performed by feathers. Protection, for example, comes right after flying. Feathers form a layer of insulation around their bodies, which guards the birds from potentially harmful ultraviolet rays of the sun. Added to this, feathers trap the air inside forming insulation against cold. This is the reason you find some birds all fluffed up on the top of your roof or on your balcony in winters.
While most of the birds give birth to the young ones, birds reproduce by laying eggs out of their body. Different species lay eggs that can be different in terms of size and color, all species however lay eggs in their respective nests. The eggs are hard shelled and provided with the right temperature before hatching by the mother itself.
Birds are often found with a rather interesting and smart habit of migrating during their breeding as well as during winter seasons. Many species of birds opt for high altitudes as soon as the breeding season arrives and come back to the low altitudes as soon as the temperature rises again. Many are found to follow a defined route of migration for years which ae known as migratory flyways
Birds make use of auditory and visual signals for communicating among themselves. These signals can be interspecific (between species) as well as intraspecific (within species). Communication via sound is done with the aid of syrinx which produces bird’s calls and sounds. These calls are made for a number of reasons including bond formation, claiming a territory, recognizing other birds as well as warning signs for predators.
It has been seen that birds like to live with close associations in a form of a group or even a large flock. Although this increases competition for potential resources, but it doesn’t go without its benefits i.e. providing safety to most members in case of the attack of the predator.
Birds have a habit of vigilant sleep where they tend to give a quick peek to the surroundings in between their periods of sleep. This helps them to counter any kind of threat and be aware of all kinds of disturbances all the time. Birds sleep with their heads bent over their back and bills tucked in their back feathers.
Birds do not have teeth and their digestive systems ae such that it allows them to process unmasticated food. Their diets mostly include fruits, nectar, plants, worms, insects, seeds and other small animals.
There are a total of around 9,865 species of birds which are divided into thirty different groups by the experts on the basis of their features, similarities, genetics, and a number of other factors.
Birds are not the only specie on earth with a capacity to fly in the air. Bats, which happen to be the mammals are capable of flying with agility as well as some of the insects which fall under the category of arthropods.