As the sun rises on another glorious day, the air fills with the sounds of tweets and twitters.
Since the fifth day of the creation of the earth, birds have welcomed the sun
each morning with their beautiful, melodious songs. Birds are a unique part of the animal
kingdom with features that make them different from any other vertebrates.
Soft, flexible, lightweight feathers are unique to birds. Feathers are made of keratin. The colors
and patterns of the feathers provide camouflage OR help a bird stand out to a potential mate.
Feathers also make it possible to do what few animals can do -- FLY!
The strong outer layer of feathers contours the body, helping birds to fly.
Many birds produce oil in a preen gland;
the oil spreads along their feathers in order to waterproof them. The inner feathers,
called down, trap warm air close to their skin and regulate the birds' temperatures.
Feathers easily wear and break, so they must be replaced regularly. Through a process called
molting, birds shed old feathers and replace them with new ones. Molts can be partial, where
only a few feathers are lost, or complete, where most of the feathers fall out at the same time.
During a molt, some birds are unable to fly. The external part of a bird’s mouth can be
called a beak or a bill, and it is made of bone covered with keratin. A beak is a specialized
tool used for building nests, preening feathers, and defending against enemies,
but most importantly, beaks are used for eating. There is great variety in the shapes
and sizes of beaks, and these differences can be clues as to what a bird eats.
Birds are bipeds, meaning they walk on two legs. Bird legs vary in shape and length to
match their behavior and environment. Some birds have short, thin legs which they use to hop,
but most of their traveling is done through flight. Larger birds, and some birds that can’t
fly, have long, strong legs that may be used for running or for thriving in their habitats.
All birds have toes with sharp claws at the ends. Some claws, as with eagles or owls, are very long,
sharp, and powerful, and they help the birds catch and kill their prey. We call these claws “talons.”
Most birds have three toes at the front and one toe in the back, though some birds, like parrots,
have two toes in front and two in back. When a tree-dwelling bird perches to rest,
a tendon that extends to the toes flexes, gripping the toes around the branch securely.
Interestingly, owls and osprey have three toes in front and one in the back when flying,
but when perching or grasping prey, the outer toe swivels to the back. The ostrich is the only bird
with just two toes: one large toe with a sharp claw, and one shorter, clawless toe next to it.
Many water birds, like ducks and geese, have webbed toes,
where a flap of skin connects the toes and forms a paddle that helps the bird to swim.
A bird's leg size and toe arrangement can be good hints about where a bird lives and how it behaves.
A bird’s forelimbs are called wings. Wings allow for flight in most bird species.
Some birds, such as storks or eagles, have broad wings and slots between their feathers
that allow them to soar high in the sky for a long span of time.
Other birds have pointed wings and quick wingbeats
that allow them to fly quickly, like peregrine falcons or ducks.
Some small birds such as sparrows or quail have short, round wings that allow for rapid
take-off and maneuverability to escape predators. Albatross, gulls, and other sea birds have long,
slender wings that allow them to soar over the water without expending a lot of energy.
Birds that cannot fly still have wings, but either the wing shape
or body size is not conducive to flight. Good vision is essential for a bird’s survival.
Keen eyesight makes up for a relatively poor sense of smell. In the animal kingdom, birds have the
keenest eyes in relation to their size. They can see in color and are able to see a wider range
of color than can humans. Birds that are diurnal, meaning active during the daytime, blink by moving
their lower eyelid up over their eyes. Nocturnal birds blink by lowering their upper eyelid.
Birds also have a kind of third eyelid called a nictitating [NIK-ti-tay-ting] membrane that helps
protect their eyes. This membrane slides from the front of their head to the back, and it moistens,
cleans, and protects the eye. The shape and positioning of the eyes of some birds allow
them to see a full 360 degrees. They can also see violet or ultraviolet light that humans cannot.
Catching sight of a bird soaring across the sky on a warm evening
brings a sense of stillness and wonder to the observer. What a view it must be
from those heights! How incredible it would feel to glide through the air on
powerful wings. The majestic bird is a beautiful reminder of the wonder of God’s creation.