How Do Animals Respond to Their Environment? · 2020-04-05 · Where do you think Snowball is hiding? Use evidence from this investigation to support your conclusion. Teachers’

Lesson 9How Do Animals Respond to Their Environment?

© Teachers’ Curriculum Institute160 Lesson 9 How Do Animals Respond to Their Environment?

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Think of what you already know about birds migrating during different seasons. Write questions you have.

Discuss: Have you ever seen a flock of birds flying together? Where do you think these birds could be going?

Observe this phenomenon: Every year, sandhill cranes fly to New Mexico.

Research a type of creature in your area that migrates. Track these migration patterns over the course of the year.

Research It!

161© Teachers’ Curriculum Institute Lesson 9 How Do Animals Respond to Their Environment?

I N V E S T I G A T I O N

Observing Phenomena

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Developing a Model for the SensesAnimals use their senses to respond to the world around them. Let’s create a model to show this process. Draw the model.

162 © Teachers’ Curriculum InstituteLesson 9 How Do Animals Respond to Their Environment?


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Setting the StageSnowball the rabbit is missing!She is Ari’s favorite pet, and he needs your help to find her.You will work as a sense detective to find her.

Here are the facts.• Ari was playing with Snowball in his room.• He went to the bathroom to wash his hands.• Ari made a sandwich in the kitchen.• Then he went to the laundry room for a new shirt.• He looked for his mom.• Ari found his mom outside setting up a picnic lunch.• He went back to his room. Snowball was gone!



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Your task is to investigate Ari’s home for Snowball. You will:

• Figure out where you are in the home.• Gather evidence from each location to help

you determine if Snowball is there.• Review our model of how animals use

senses to respond to the world. Use this model to predict how Snowball might respond in each location.

• Construct an argument based on your observations about where Snowball is hiding. Then, predict where she is.



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Gathering EvidenceTime to visit Ari’s home.At each station:• Reach into the bag and feel the item. Wash your hands before and

after.• Look at the placard from each location.• Hold each bottle opening about 5 cm (2 in.) away from your nose.

Gently squeeze the bottle and waft the air until you can smell something.

Complete the first three rows of the tables below.Be a sense detective and find Snowball the rabbit. Visit Station A.

Station ADescribe what

you sense.

Snowball’s brain would interpret this item as…

Snowball’s brain would give

instructions to react by…

Touch

Smell

Sight

Sound

Taste



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Be a sense detective and find Snowball the rabbit. Visit Station B.

Station BDescribe what

you sense.




Touch

Smell

Sight

Sound

Taste



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Be a sense detective and find Snowball the rabbit. Visit Station C.

Station CDescribe what

you sense.




Touch

Smell

Sight

Sound

Taste



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Be a sense detective and find Snowball the rabbit. Visit Station D.

Station DDescribe what

you sense.




Touch

Smell

Sight

Sound

Taste

You still have to get evidence for each station by hearing and tasting.

Listen to the sounds played to you by your teacher. Then, fill out the Sound rows above for each station.

Finally, we’ll gather evidence with taste. View a picture of an item from each station. Imagine how it will taste. Then, fill out the Taste rows for each station.



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Examining the EvidenceNow, examine the evidence you gathered. What are the four locations?

Where do you think Snowball is hiding? Use evidence from this investigation to support your conclusion.



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Vocabulary

My Science Concepts

Reflect on your understanding. Draw an X along each line.

Animals receive many different types of information as stimuli from the environment. Stimuli include light, touch, sound, temperature, and substances that can be tasted.

still learning know it

Models are general descriptions of scientific principles, which can be used to construct explanations of specific phenomenon.


Senses can be modeled as information received from the environment, processed by the brain, and then responded to. This model explains how an animal responds to seeing movement, hearing a sound, feeling a change in temperature, or any other sensory input.


Match the term to the correct definition.

Word Bank

brain memory spinal cord behavior

1. The way an animal acts.

2. A long bundle of nerves that connects the brain to the rest of the body. The spinal cord lies inside the backbone, which protects it.

3. Information stored in an animal’s brain.

4. An organ in the nervous system that is the control center of the body.



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1. The Brain Controls the Body’s Activities

Suppose a wolf sees a deer. Its eyes send messages to its brain, and the brain responds by sending messages to the rest of its body. The wolf chases the deer, pounces, and brings down its prey.

An animal can respond to stimuli because its sense organs work closely with its brain. The brain is the organ that is the control center of the body. The brain is very important, so it is protected by bones that make up the wolf’s skull. Messages travel from the sense organs to the brain. The brain interprets them and sends messages to the muscles that tells them how to respond.

Wolf brains have three main parts. Each part has its own functions. The largest part of the brain is the cerebrum. It controls muscles in body parts that the wolf wants to move, such as its legs or jaws. This part of the brain also controls memory, learning, and thinking. Information from the sense organs goes here.

The second part of the brain controls the wolf’s balance. It is called the cerebellum. It also lets the wolf stand up and walk around without needing to think about it.

The third part of the brain, the brain stem, controls all the functions the wolf’s body needs to stay alive, such as breathing and digesting food. The wolf does not have to think about these functions. They happen automatically.

A wolf’s brain is very similar to yours. Different parts of its brain control different activities.

This wolf is standing up and breathing. Its cerebellum and brain stem control these actions so the wolf does not have to think about them.


T E X T W I T H N O T E S

A Wolf’s Brain

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Write a short story about a wolf. Include at least three examples of the wolf using different parts of its brain. Include these terms in your answer: cerebrum, cerebellum, and brain stem.



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2. Nerves and the Spinal Cord

Since a wolf’s brain controls its body, how do you think it sends messages to the muscles? How does it receive messages from sense organs?

A nerve is a structure that carries messages from one part of the body to another. Some nerves carry messages from sense organs to the spinal cord and brain. Other nerves carry messages from the brain and spinal cord to muscles.

The spinal cord is a long bundle of nerves that ties the brain to the rest of the body. It runs inside the backbone, which protects it. Many nerves branch off from the spinal cord. The nerves, spinal cord, and brain are all parts of the nervous system.

The nervous system helps animals react to stimuli, such as when a wolf hunts a deer. Receptors in the sense organs collect stimuli from the environment. Nerves carry messages from the wolf’s sense organs to its brain and spinal cord. If a wolf smells a deer, nerves carry a message about the deer to the wolf’s brain. Other nerves then carry messages from the wolf’s brain and spinal cord to its legs. The messages tell the leg muscles to move the legs toward the deer. Then the brain sends messages to the wolf’s jaw muscles to bite the deer. The wolf’s nervous system and muscles work together to hunt the deer.

This is a human nervous system. Nerves run throughout the whole body, so the brain can receive and send messages to every part of the body.

A wolf’s nervous system is composed of its brain, spinal cord, and nerves. The brain can send and receive messages from the whole body.



A Wolf’s Nervous System

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Describe in your own words what happens inside a wolf’s body when it sees a mouse. Use these terms in your answer: brain, spinal cord, legs, message, nerves, and eyes.



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3. Instincts

If someone throws a ball at you, you react without thinking. Your body knows what to do to keep you from getting hurt.

Behavior is the way an animal acts. A behavior can be a response to a stimulus, such as hunting for food when hungry. Most behaviors that help an animal survive do not have to be learned. A behavior that an animal is born knowing how to do is called an instinct. For example, a mouse is born knowing how to run away from a snake. The mouse also knows that it should eat fruit and insects, even if it has never seen them before.

Many birds are born with the instinct of knowing that they should fly to warmer areas when it gets cold outside. Ducks living in Canada are born knowing they should fly south when it starts getting cold, even if it is their first winter.

Many spiders spin webs to trap insects. Each kind of web-spinning spider spins a web with a different shape. A funnel spider spins a web that is shaped like a tube. An orb spider’s web has circles with lines crossing them. Each spider knows how to build only one type of web, and they know how to build this web when they are born—it is an instinct.

Spiders are born with the instinct of knowing how to spin one type of web. A funnel spider spins a funnel-shaped web and an orb spider spins a round web. Neither spider can spin the other’s kind of web.



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What are some instincts that you think humans are born with? Brainstorm at least two instincts.



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4. Reflexes

All instincts involve the brain. Sense receptors pick up stimuli from the surroundings. They send messages to the brain. The brain must figure out each message before sending a message to the muscles. This process takes time.

But not all behaviors involve the brain. A reflex is a behavior that does not involve the brain. Many reflexes keep animals out of danger. For example, if someone throws a ball at your face, you blink. Blinking is a reflex that protects your eyes. Your brain is not involved in blinking. Another common reflex is sneezing. Reflexes are usually simpler than instincts.

How does a reflex work? If you touch a hot object with your hand, heat and pain receptors in your skin detect the stimuli. The receptors send messages to the spinal cord. The spinal cord quickly sends a message to your arm muscles, and you pull your hand away. Because the messages do not have to be processed in the brain, a reflex is much faster than an instinct. A reflex occurs before the brain is aware of what happened. Your brain learns of the movement of your hand after the response takes place. However, your brain cannot control the movement.

When you touch a hot object, a reflex moves your hand. Your receptors in the skin send a message about the object to your spinal cord, which sends a message to your arm muscles to move your hand back.

A Human Reflex



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What are some reflexes that you think humans have? Brainstorm at least two reflexes.



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5. Learned Behavior

When you were young and first held a book, you could not read the words. It took a long time before you learned to read. You had to practice before you could read as well as you do now. Reading is a learned behavior.

Many behaviors and responses have to be learned and practiced. Baby chimpanzees are born with few skills. As the baby chimpanzee grows and develops, it must learn how to find food and feed itself. It must learn how to take care of itself. It learns how to use a rock as a hammer to break open nuts and how to use a stick to dig insects out of the ground.

Both you and the chimpanzee learn by watching others or by being taught. A teacher probably taught you how to read in school. You learned how to read from the teacher. You probably learned other skills from your parents or friends. Learning happens in the brain.

Animals must practice a learned behavior until they can do it well. For example, young tigers practice sneaking up on prey. They learn from their parents to be good hunters. Animals can also learn by trial and error. A mouse in a maze makes many wrong turns before it learns the right path out of the maze. Next time, it goes through the maze faster because the mouse has done it before.

This chimp is using a stick as a tool. It learned how to use this tool from its parents.



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What might this chimp be using the stick for? Where do you think it might have learned how to use it? Use these terms in your answer: learned behavior and tool.



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6. Memory

Have you ever seen a mouse in a maze? Each time the mouse goes through the maze, it can solve it faster. Why do you think that is?

Each time an animal senses something, it forms a memory. Each time an animal does something, it also forms a memory. Memory is any information stored in the brain. For example, animals might remember what a plant smells like. They might also remember where they like to hunt. Forming and using memories is very complicated. Many structures work together to make memories, like the brain and other structures of the nervous system.

When an animal repeats the same behavior, it is forming stronger memories. The behavior improves with each practice. For example, a baby lion is not very good at hunting. But every day, the lion practices hunting. Soon, it has hunted many times. Each time it went hunting, it used its memories to become a better hunter.

Some animals can remember exactly where they hatched, even then they are old. For example, Pacific salmon are born in rivers near the ocean. When they are a few years old, they swim to the ocean. As adults, the salmon return to the exact same river where they hatched. Salmon can remember exactly what the river they were born in smells like!

This salmon has spent many years living in the ocean, but it still remembers where it hatched. When it is older, it returns to the very same river where it hatched.



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Look at this deer living in the woods. What are some things it might form memories of?



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Show What You Know

Animals receive many different types of information from their sense organs.a. Complete the diagram below to show how an animal might respond

to something hot. Use these terms: heat, nerves, muscles, pull away, reflex, skin, and spinal cord.

b. Then draw a diagram to show how an animal might respond to the mouse stimulus. Include these terms in your diagrams: brain, muscles, response, and sense organ.

AHot object

senses pain

and .

Receptors send message along

to

.

Spinal cord sends message to

arm to

.

This response is a .

BMouse


C H E C K F O R U N D E R S T A N D I N G

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Making Sense of the Phenomenon

Claim

Evidence

Reasoning

Use your findings from the investigation to answer this question:

How do sandhill cranes respond to their environment?

Go back to page 4 and fill out the unit checkpoint for this lesson.

Let’s revisit the phenomenon: Every year, sandhill

cranes fly to New Mexico.

Think about:• How do the cranes know to migrate?• Explain how this behavior helps the cranes survive.


C H E C K F O R U N D E R S T A N D I N G

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N O T E S

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Documents

How Do Animals Respond to Their Environment? · 2020-04-05 · Where do you think Snowball is hiding? Use evidence from this investigation to support your conclusion. Teachers’