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Birds have a long and intriguing evolutionary history, with the
earliest known ancestors descending from reptiles over a hundred and thirty
million years ago. These early birds had lizard-like tails and teeth in their
jaws, but over millions of years, their wings evolved and their teeth
disappeared. Today, there are over 8,500 different species of birds, each with
unique characteristics and habitats.
The world can be divided into six formal regions where a large proportion of
birds are found, but these divisions are not always definitive. For example, the
oyster-catcher can be found in both New Zealand and Britain, while the house
sparrow and starling are common in most parts of Britain except Scotland. The
Wallace Line, named after the explorer and naturalist Alfred Russel Wallace,
divides the birds of Bali and Lombok, even though they are only twenty miles
apart.
Flying birds are built for an active life with muscular bodies, hollow bones, a
sharp keel, and a powerful heart. Their feathers are not only attractive and
bright, but they also assist in flight and keep the bird warm. Mating and
courtship are purely instinctual, and after the cock-bird claims his territory
with aggressive songs, the pair builds a nest, lays eggs, and incubates the
young. Migration is another shared habit among birds, with many traveling
thousands of miles to breed and feed.
Birds play an important role in the lives of humans. Some birds are considered
pests, while others help to control insect populations and provide food in the
form of meat and eggs. Wild fowl also provide a source of sport and game, while
feathers are used for various purposes such as hats or insulation. Finally, the
beauty of birds, whether it be the melodious songs of the nightingale or the
vibrant plumage of the peacock, never fails to delight and uplift people's
spirits.
In conclusion, birds are fascinating creatures with unique evolutionary
histories and habits. They inhabit nearly every corner of the globe and play
important roles in the natural world and in human society. |
