TOPIC: BATS
LEVEL: Intermediate/Advanced
"The Wings of Bats"
[information |
preparation |
activity ]
- SCIENCE CONCEPT:
-
A bat's wing consists of bones that are very similar to
the bones in a human arm and hand. Long arm bones, with extra-long
extended finger bones, are covered with a double layer of thin skin
called a membrane. The second and third fingers, along with the membrane
in between, give the wing a stiff leading edge similar to an airplane's,
while the third finger forms the wing tip.
- STUDENT OBJECTIVE:
-
The student will draw the wing of a bat, a bird wing,
and the arm of a human to show the similarities and differences between
the three of them.
- OVERVIEW:
-
As the student draws the wing of a bat, the wing of a bird,
and a human arm they will observe the similarities in the three. The
student will also ascertain the differences between the three of them and
what makes each unique. Both bats and birds have mastered flight with
their wings.
- TEACHER TEXT:
-
The name given to bats is the animal order: "chiroptera" is Greek for handwing. Long arm bones, with extra-long extended
finger bones, are covered with a double layer of thin skin called a
membrane. The membrane is so thin that you can see light through it. It
is made up of fine blood vessels, elastic fibers and muscle fibers. The
fibers help keep the flight membrane taut and aid in folding of the wing
membrane when the bat is at rest.
The membrane stretches over the arm bones and extended
finger bones to the sides of the body and leg forming an airfoil surface.
In some bats, this flight membrane may also extend between the legs and
include the tail. The small clawed thumbs (often used for climbing) are
left free. The second and third fingers, along with the membrane in
between, give the wing a stiff leading edge similar to an airplane's,
while the third finger forms the wing tip.
A bat's wings act like webbed hands. The bat can move
its wings like we move our fingers enabling it to change its wings' shape
rapidly to dart, flip, and turn quickly. Although birds use their tails
to brake and steer, bats use their wings by folding one wing for a second
and using one independently of the other. Many bats have also mastered
hovering flight, similar to hummingbirds and helicopters, that enables
them to remain stationery in flight, while other bats are able to achieve
brief periods of gliding flight.
PREPARATION TIME: 15-20 minutes
LESSON TIME: 25 minutes
TEACHER PREP:
-
Gather pictures of a bat's wing, a bird's wing, and the
arm of a human showing the bone structure of all three, along with their
outlined form.
WORDS TO KNOW:
- chiroptera
- handwing
- membrane
- muscle fibers
- clawed thumbs
- webbed hands
MATERIALS NEEDED:
- Pictures of the skeletal frame of the bat wing, bird wing, and human arm
- paper
- pencils and erasers
- colored marking pens
- STEPS TO FOLLOW:
-
1. Show and discuss the pictures of the skeletal frames of the bat wing,
bird wing, and human arm. Discuss the similarities and differences.
Display these pictures clearly so that the students can refer to them as
they draw.
-
2. Pass out artist drawing paper, pencils, erasers, and colored marking
pens.
-
3. Ask the students to draw the bat wing, bird wing, and human arm with
the skeletal bones distinguished in colors along with an outline of the
shape of them.
Suggestion: Have the students color the arm bones in all three in
yellow, the hand bones in each red, and the finger bones in the bat's
wing, bird's wing, and human arm in blue.
-
4. Have the students share their drawings in front of the class pointing
out the similarities and differences between the bat's wing, bird's wing,
and human arm.
Have the students explain why a bat and a bird can fly with their wings
if possible.
- WHY?
-
The bat's wing is a fascinating structure that has
similarities to the wing of a bird and a human arm. Without the wonder
of the structure of the bat's wing it could not fly. There are obvious
differences as well between the bat's wing, the bird's wing, and the
human arm. The wing of the bat has a thin membrane covering, and not
feathers like birds do. And the arm of a human being is altogether of a
magnificent form that distinguishes him from the animals.
- ASSESSMENT: Can the student communicate what they observed?
-
4....Student is able to communicate all of the similarities and
differences between a bat's wing, a bird's wing, and a human arm.
-
3....Student is able to communicate most of the similarities and
differences between a bat's wing, a bird's wing, and a human arm.
-
2....Student is able to communicate some of the similarities and
differences between a bat's wing, a bird's wing, and a human arm.
-
1....Student is able to communicate one of the similarities and
differences between a bat's wing, a bird's wing, and a human arm.