
Oh, Behave!
Adults have probably told you to behave more
than once. They usually want you to stop doing something undesirable. Maybe
you were making faces at the dinner table or goofing off in the classroom.
In science, behavior is the way an animal or
person responds to others and the environment. Plants also
show various behaviors, as do non-living things such as magnets, electricity,
and the weather.
Behavior in the Animal Kingdom
The behavior of animals is most familiar.
A behavior can be as simple as avoiding something unpleasant or seeking out
something pleasant. Single-celled organisms such as paramecia seek
food. This is a behavior. A paramecium will also try to avoid predators.
More complex animals have more complex behaviors. Some birds,
for example, dance, prance, and display their feathers in
courtship rituals. The male that does the best job of catching the eye of the
female wins her as a mate.
Behavior includes pretty much everything that helps an animal survive. Communication,
interaction with others, and reactions to the environment are all behaviors.
Staying Planted
Plants have various behaviors, too. Plants
show that behaviors aren’t always the result of choices a living thing
makes. For example, plants can’t uproot themselves and move to a sunnier
spot, but they will grow toward the sun.
Growing toward the sun is a behavior that helps plants survive.
Predictable Properties
A magnet doesn’t choose to attract
metal, but that’s how it behaves. Scientists are able to make predictions
about the weather thanks to the way air behaves at different temperatures.
Because electricity always flows through a conductor,
such as a metal wire, we are able to use electricity to light and heat our
homes. These behaviors are dependable, which makes them useful to us. Elements have
specific melting, freezing, and boiling points and so do compounds such as
water. Water in its solid form (ice) melts at 0° C.
At 100° C,
water boils and turns into a gas called water vapor.
Why are we able to count on these substances behaving in these ways? Because
their physical properties direct
their behavior.
A substance’s chemical properties also affect its behavior
in predictable ways. The element iron, for example, changes to form a new substance—rust—when
exposed to moisture and oxygen. Gold, on the other hand, does not change at
all when it comes in contact with moisture and oxygen. This is because its
chemical makeup is different from the chemical makeup of iron.
Forces Beyond Our Control
An object’s behavior may also be controlled by outside forces.
The force of gravity,
for example, has an effect on the behavior of everything on Earth.
It’s because of gravity that water flows downhill, plant roots grow down,
and your feet stay planted firmly on the ground.
If non-living things began behaving in unusual or unpredictable ways, we’d
have many troubles. For instance, we count on gravity to pull everything toward
Earth. Otherwise, we might go floating off into space! We expect certain weather
patterns because of the predictable behavior of the atmosphere.
Changes in that behavior might harm crops, dry up water sources, or cause severe
storms.
Basic Instincts
Behaviors in animals can be voluntary or involuntary.
If someone throws a ball of paper at you, you raise your hand to catch it or
bat it away so that it doesn’t hit you. This behavior is an instinct.
Instincts are not things you choose to do. They are behaviors that happen without
you even having to think about them.
Animals are born with the instincts to do certain things such as eat, sleep,
and avoid pain. The brain and nervous system control instincts (and all behavior).
Here’s an example. When it’s dark outside, a cat’s brain
directs its pupils to
open wide. This allows as much light as possible to enter the eyes. This helps
the cat to see.
Learning to Be Choosy
Other animal behaviors are learned and voluntary. Humans learn behaviors such
as walking, talking, and sharing. Voluntary behaviors are behaviors a person
or animal chooses to do. You choose whether or not to raise your hand and answer
a question in class. A tiger chooses the right moment to pounce on prey.
Voluntary behavior can also be influenced by the environment and by others.
A giant
panda, for example, will walk farther if it can’t find enough bamboo
to eat in one area. People smile at other people they like.
The Key to Survival
Behavior is basic to the survival of living
things. Plants and animals have adapted to
behave in ways that help them find food, give birth to more young, and avoid
harm. The more successful the behavior, the more successful the animal will
be in life. An example is “playing possum.” When threatened by
a predator, a Virginia opossum will fall over and stop moving. Its breathing
slows way down. The predator may be fooled into thinking that the possum is
dead and will then leave it alone. Once the danger has passed, the opossum
gets up and goes about its usual business. This behavior has helped opossums
survive for at least 70 million years. In fact, opossums have been around longer
than almost any other mammal.
For the Good of the Group
Behavior is also an important part of animals’ social
structures. Wolves, for example, live in complex social groups called packs.
The wolf-in-charge is known as the pack leader or alpha male. Other pack members
follow his lead in hunting and in everything else the pack does. A pack leader
will remain in charge as long as he is healthy and makes good choices for the
pack. Wolves must work as a group and share the jobs of hunting and raising
pups. Cooperative behavior is important if the pack is to thrive.
Human social interactions aren’t so different from those of wolves.
Wolves communicate with body language and barks. We communicate with words.
We also live and work in groups (families, communities, and nations, for example).
We must cooperate to get along well in life. This is why behavior that is not
acceptable can be a problem for individuals and others. You can think of rules
and laws as “behavior guidelines.” People agree that certain behaviors
are so undesirable that they need to be outlawed. Stealing and hurting others
are two such behaviors. Desirable behaviors are those that help everyone get
along and be happy.
Studying Behavior
What we know about behavior of both living
and non-living things comes from observation and scientific experiments. Physics
is the study of the behavior of matter and energy.
Chemistry is the study of how chemicals behave and interact. The behavior of
the stars and
planets is part of the work of astronomy.
Some behaviors of non-living things are so dependable that there are scientific
laws that describe the behaviors. For example, English scientist Isaac Newton
(1642–1727) developed the laws of motion. One law of motion states that
for every action there is an equal and opposite reaction. That’s why
you can count on a toy car rolling away from your finger if you push it.
Unraveling the Mysteries of Animal Behavior
Behavior of animals and humans isn’t quite as certain and predictable
as, for example, the laws of motion. But through careful observation, scientists
have made many important discoveries. British zoologist Jane
Goodall learned about chimpanzee behavior by quietly watching them for many
years. She was the first to discover that chimps use tools. She also learned
that they hunt and eat meat.
Scientists also discovered that crows use—and even make—tools.
As an experiment, scientists put a treat inside a box. Then, they gave the
crows nothing but a stick that was too short to reach the treat. Inside another
box, though, was a longer stick. The crows surprised scientists by using the
short stick to reach the longer one. Once they had the longer stick, they were
able to reach the treat in the box.
Behavior and Conservation
Studying animal behavior may help conservationists protect
rare animals from extinction.
For example, knowing that young birds will follow the lead of human caretakers
is helping whooping cranes learn to migrate even
though there are no adult whooping cranes to teach them. The birds follow a
human “parent,” who flies the migration route in a small plane.
They travel more than 1,600
km. Having more migrating cranes in the wild may help this rare bird survive.
Behavior and Social Problems
The study of human behavior crosses many areas of science. Doctors and psychologists study
how the brain directs behavior. Sociologists study social behavior. One thing
people who study behavior do is try to understand why people have conflicts.
They may also study what causes dependence on drugs or alcohol or why criminals
break the law.
Understanding behavior is important for understanding ourselves. It is the
key to understanding how people deal with problems such as climate
change, poverty, war, and disease.
Learning how to treat behavior problems can help people live happier, more
useful lives.