It
is estimated that birds evolved from some species of reptiles in the
past, which shortened his front paws and a special hair grow in the
body. At first, primitive wings which is the development of front claws
that can not be used to actually fly, and just helped to hold the
altitude to a lower place.birds today have evolved in such a way that is
specialized to fly away, with the exception of some primitive types.
Feathers, especially on the wing, has grown increasingly wide,
lightweight, strong and tightly tiered. The feathers are also
stratified in such a way that can hold water, and maintain the bird's
body kept warm in the cold. Bones become lighter because of the air
cavity inside it, but still supports a strong body. Chest bones grow
larger and flat, as an attachment to the flight muscles strong.All this
makes the birds more easily and more clever fly, and was able to visit
various habitats on earth. Hundreds of bird species found in tropical
forests, they inhabit these forests from coast to mountain tops. Birds
are also found in swamps, grasslands, coastal, ocean, rock caves,
urban, and polar regions. Each species adapt to the environment and its
main food.
Then known various kinds of birds of different colors and shapes. There
are light or bright colors jet black, leaf green, dark brown or mottled
for camouflage, and others. There's a strong beak for tearing flesh
(Eagle), fruit seeds hard crisis (Bird Manyar), points to spear fish
(Bird Kormoran), flattened to filter sludge (Duck), wide to catch flying
insects (Bird ordinary eyeglasses), or slightly longer to suck nectar
('Ō'ō Kaua'i). Some have sharp claws for grasping prey, claws climbing
trees, soil and trash-digging claws, webbed paws for swimming, strong
claws to run and rip the belly of his enemy.
