The Flight of Birds

SCIENCE CONCEPT:

Birds have certain characteristics that set them apart from other animals. They have adapted to their environment, making them prime subjects of flight. There are many reasons why birds are able to fly.

STUDENT OBJECTIVE:

The student will be researching the characteristics of birds, their adaptations to the environment, their wonderful ability to fly, and why they are important to us.

OVERVIEW:

Think for a moment about the variety of birds that you have seen. Every bird has its own special color and flight ability. There are many kinds of birds, yet they have certain basic characteristics. Birds are well adapted for flight because they have two wings, have lightweight bones, and breathe through lungs. Each kind of feather on a bird serves a different purpose. Soft down feathers grow close to the skin. Air is trapped between the spaces of these down feathers. The bird's body gives off heat that warms the air in these spaces. Over the down feathers is a second kind of feather that rounds out a bird's streamlined body. A third kind of feather, the large flight feathers, grow in the wings and tail. The flight feathers give birds the lift and balance needed for flying.
The energy needed for flight comes from food and a steady supply of oxygen. Birds' lungs branch into hollow spaces called air sacs. Air from the lungs is pumped down through the air sacs. The air sacs connected to the lungs supply oxygen during flight. Most birds secrete an oily substance which they use to coat their feathers. This is called preening and prevents water from penetrating their feathers, thus making the birds buoyant. Birds' feathers are replaced at least once a year by molting.

PREPARATION TIME:

30 minutes.

LESSON TIME:

45 minutes.

TEACHER PREP:

Obtain pictures or slides of a variety of birds in flight, a live bird, three different kinds of bird feathers (down, contour, and flight), and different bones such as chicken, pork, beef and bird.

WORDS TO KNOW:

air sacs

lift

balance

streamlined

hollow

down feathers

contour feather

flight feathers

respiratory

preening

molting

TEACHER TEXT:

There are many things about birds that make them good subjects for study. They are very abundant, so they are easily observed. They adapt easily to captivity and experimentation. Their great diversity with beautiful colors, characteristic songs, and unique habits makes each species easily identifiable. In fact, it is probably the great diversity among birds that enabled scientists to truly understand the complex combinations each species possesses and still achieves flight. Every thing about every bird is designed for flight no matter what combination of attributes they possess.

In order to understand natural flight in birds, one must examine the structure of a bird. Exactly what makes a bird a bird? They all possess common characteristics. Birds are unique in the animal kingdom for two reasons. First, all birds have feathers. And second, all birds live in a hurry. Everything about a bird is fast: they breathe faster than any other animal, their heart beats faster, and their body temperature is higher.

As inhabitants of the earth, birds have a special place in the ecological world. They play a vital role in the balance of nature: eating insects, agricultural pests, and other small animals; while they, in turn, are eaten by many larger animals. Fruit eating birds, because they do no digest seeds, are the primary seed dispersal mechanisms for many plants. Hummingbirds help pollinate nectar producing flowers. Seed eating birds do digest seeds, and by so doing, eliminate millions of weeds from the earth. For man, birds have other values as well. They are sources of protein as both eggs and meat. Feathers are used for pillows, quilts and clothing.

Web Hosting Provided By The National Business Aviation Association.

Explore Space ... Not Drugs!
Hear what astronauts have to say about staying drug-free.
Last modified: Sat Aug 23 14:04:12 PDT 1997