Download Chapter 15.1b

CHAPTER 15.1B
Birds
WINGS
Not all bird fly, but most wings are used for flight.
Wing are attached to powerful chest muscles. Birds
will flap their wings to gain thrust and go forward,
lift, and stay in the air. Wings will move up and
down, and back and forth.
The shape of the birds wings will help it fly. Wings
are curved on top and flat or slightly curved on the
bottom.
When a bird flies the air below the wing moves
slower than air on top of the wing. This creates
greater pressure on the bottom of the wing pushing
the wing up.
Larger wings allow birds to be able to soar and
glide without beating their wings.
Birds that don’t fly use their wings to swim or in
courtship, or to maintain balance.
DIGESTIVE SYSTEM
Birds need a lot of high energy food, like
nuts, seeds, nectar, insects, and meat, so they
can fly.
Food is broken down quickly in the digestive
system to get energy.
From a bird’s mouth the unchewed food
moves to the crop. This is an area that will
store food until it absorbs enough moisture to
move on. The food then enters the stomach
where it is partially digested. It then moves
into a gizzard. The gizzard grinds and
crushes, with small stones, the food. Digestion
finishes in the intestine and then the nutrients
move to the blood stream.
RESPIRATORY SYSTEM
Body heat is made when food is
combined with oxygen. A bird needs a
good respiratory system to get energy.
Birds have 2 lungs. Each lung has
balloonlike air sacs. Air flows one
direction in the bird’s lungs. The receive
air with oxygen when they inhale and
when they exhale. This gives a constant
supply of oxygen.
CIRCULATORY SYSTEM
A bird has a heart, arteries, capillaries,
and veins.
They have a large 4 chambered heart.
A bird has a very fast heartbeat.
THE IMPORTANCE OF BIRDS
Birds can be a source of food and raw materials. Many birds are kept as pets.
Owls help controls pest by eating rodents.
Many birds eat insects and help keep insect populations in check.
Other birds are pollinators. They also help disperse seeds for plants.
Birds can be pests when they have a large population and their droppings causes a
lot of damage.
USES OF BIRDS
Humans hunt birds for food or fancy feathers.
Many birds have been domesticated to be used for meat and eggs (turkeys and
chickens).
Feathers are used in mattresses and pillows. Down feathers are good insulators.
Bird droppings can be used as fertilizer.
VISUALIZING BIRDS
Birds look very different based on what they
eat.
Birds of prey have large claws and sharp
beaks because they eat meat.
Seed eaters have a strong beak to crack
seeds.
Insect eaters have a point beak that can pry
bark or bore wood to find insects.
Waterbirds have webbed feet that help
them move through water.
Flighless birds can be fast runners.
Wading birds usually have long legs so they
can walk in shallow water.