Life of Animals

Sangari Active Science, 2nd Edition

Student Lab Manual

Published by Sangari Active Science, 44 Amogerone Crossway #7862, Greenwich, CT 06830.

ISBN: 978-1-940901-56-5

Need help? Email us at support@sangariglobaled.com

For more information on our products and services, please visit us online at

http://www.sangariglobaled.com

The publisher of this book has used its best efforts in preparing this book.

The publisher makes no warranty of any kind, expressed or implied, with regard to the programs or documentation

contained in this book. The publisher shall not be liable in any event for incidental or consequential damages

in connection with, or arising out of, the furnishing, performance, or use of these programs.

Copyright © 2014 Sangari Active Science. All rights reserved. Printed in the United States of America.

Life of AnimalsWork designed and produced by Sangari Research and Development Center

Life of Animals

Dear Student,

You probably already know some things about animals. Maybe you have a pet. Maybe you’ve been to a zoo. Maybe you live on a farm or have visited one. Maybe you have watched TV programs or investigated animals on the Internet or in books. Are you old enough to have learned that sometimes, the more you know about something, the more you want to know? As you get older, you ask different types of questions. Different aspects of the world around you start to interest you.

As you study the life of animals, you are probably going to learn some new things about animals and their habitats. Perhaps you will think of new questions. Maybe you will be able to share ideas you have heard or read outside of class. Get ready to ask your questions and to see what new things you can learn about how animals interact with each other and with the environments in which they live.

The Sangari Active Science Team

Table of Contents11 Lesson 1

How Do Animals Adapt to Their Environment?

17 Lesson 2

How Do Particular Structures Allow Animals to Survive?

25 Lesson 3

How Do Habitats Meet an Organism’s Basic Needs?

31 Lesson 4

How Do Organisms Depend on Their Environments for Food?

37 Lesson 5

How Are Life Cycles Dependent on Habitats?

43 Lesson 6

How Do Animals Coexist for Survival?

51 Lesson 7

What Happens to Animals When an Ecosystem Changes?

59 Lesson 8

How Do Humans Affect Ecosystems?

66 Glossary

SafetySangari Active Science

Safety is important. During science activities, make sure to pay attention to the following safety symbols in your Student Lab Manual.

Follow these safety tips:1. Follow your teacher’s instructions.

2. Do not touch your face, eyes, nose, or mouth during investigations.

3. Do not mix things together to see what will happen.

4. Tie back long hair, and roll up sleeves before doing investigations.

5. Move everything out of the way that you do not need for science.

6. Tell your teacher right away if you have any accidents or spill anything.

CU

clean upDT

don’ttaste

SO

sharpobject

ES

energy source

WH

wash hands

PM

poisonous material

GO

weargoggles

10

LESSON 1

What is the pelican doing?

How does the pelican’s beak help it survive?

How DoAnimals

Adapt to Their Environment

11

Lab ActivityBird Beaks

Look at the images of the birds. Discuss the different types of beaks with your class. Compare the materials you will use with the bird beaks in the images.

Your teacher will hand out one type of “beak” to each team and choose one member to hold the beak and act as the “bird.”

Place a handful of rubber bands on the desk. The “birds” will have 30 seconds to use their “beaks” to pick up the rubber bands and put them in the clear cup.

Begin when the teacher gives the signal.

When time is up, count how many rubber bands the “bird” was able to pick up. Which kind of “beak” picked up the rubber bands the fastest? Record your fi ndings in your Science Notebook.

Choose another member of your team to be the “bird.”

Repeat Steps 2 through 5 with all the other items your teacher gives you to test.

Just as there are many different species of birds, there are many different types of bird beaks. The following images show different species of birds and the beaks they use to eat food.

12 Life of Animals

1

Eagles and other raptors have strong, hooked beaks for tearing fl esh.

Anhinga and herons are birds with dagger-like bills that are good for spearing fi sh and frogs.

Pelicans have large, strong, pouched beaks that can be used for scooping up water and fi sh.

Hummingbirds have long, thin beaks and straw-like tongues that help them drink nectar from fl owers.

Woodpeckers have chisel-like beaks for breaking through wood and searching under tree bark to fi nd insects.

Snipes have long, thin beaks that are good for probing in mud and water to fi nd worms and other small animals.

13Lesson 1 How Do Animals Adapt to Their Environment?

Learn MoreAnimal SheltersAnimals use resources from their environments to meet their basic needs. The following images and captions will help you learn about ways some animals use resources to find or make shelters.

Some types of wasps make paper nests such as this one. The wasps chew rotting wood that they mix with their saliva. After the wood is chewed enough, it turns into a paper-like pulp they use to create nests. You may have seen a wasp nest hanging from a tree or another location.

Termites build nests for shelter against predators. They design their nests to also catch water and moisture for survival. Many termite nests are underground. However, some termites build mounds above the ground, as shown. Termites have adapted to survive even in hot, dry climates. The mounds are made from mud, soil, chewed wood, and saliva. These mounds can be very small or up to 10m tall. Termite nests have many chambers. They use different chambers for hatching eggs and for growing fungi that they feed on.

Having a safe shelter is an important part of a bird’s ability to live in its ecosystem and meet its basic needs. Birds often use twigs, leaves, and other materials to build nests for their fragile eggs. Some birds, such as the one shown, make their nests in holes in the sides of trees.

14 Life of Animals

1

Beavers are known for building in rivers and streams. Their shelters are called lodges. Lodges protect beavers from predators such as coyotes and wolves. Lodges also help beavers trap food. Beavers have adapted to use their paws and mouths to carry the mud, rocks, and sticks they use to build lodges and dams. Some beaver dams are small like the one in this photo. However, dams can be almost a kilometer long and more than three meters tall.

Do you know any animals that use caves as shelters? The moray eels in this photo hide and live in underwater crevices and alcoves. These shelters protect them from predators. They also allow moray eels to surprise the prey that they are hunting.

15Lesson 1 How Do Animals Adapt to Their Environment?

16

LESSON 2

How Do Particular

Structures Allow

Animals to Survive?

How does hair help animals survive?

What do feathers do for birds?

17

Lab ActivityStructures of a Feather

What is the function of feathers, hair, and scales for animals?

A. Write your ideas in the Predict section of your Science Notebook.

B. Share your ideas with your team.

A. Identify the structures in the feather.

● barbs – part of a feather connected to the rachis

● barbules – part of a feather connected to the barbs, containing small hooks

● quill – bottom, hollow part of a feather

● rachis – main shaft of a feather

● vane – part of the feather than contains barbs and barbules

B. Compare the down feather to the long feather. What do you notice about the parts of each type of feather?

Quill

Vane

ill

Shaft or Rachis

Barbs

Barbules

Hooks

achisShaft or

H

Ba

HoH

arbBa

18 Life of Animals

2

How do barbs unite to keep the feather organized?

A. Observe your teacher demonstrating how to pass the feather between your fi ngers in order to organize its structure.

B. Carefully pass the feather between your fi ngers from the tip to the quill (bottom). Use a magnifying glass to examine the feather closely.

C. Describe the notable components of the feather. Record your observations and descriptions in your Science Notebook.

D. Pass the feather in the opposite direction, from the bottom (quill) to the top. Use a magnifying glass to examine the feather closely again. How does the feather look? Record your observations in your Science Notebook.

19Lesson 2 How Do Particular Structures Allow Animals to Survive?

Learn MoreSkin Appendages The skin has many purposes. It protects the body from losing or gaining too much water. It protects the body from the invasion of bacteria. Specialized structures called skin appendages help animals survive in their environments. Examples of skin appendages are whiskers and hair, feathers, horns, claws, scales, and some types of glands, such as mammary glands that produce milk for offspring.

Whiskers and hair are attached to the skin of some animals.

20 Life of Animals

2

In the hedgehog, the hairs are rigid structures adapted as spines for defense.

Hair is one skin appendage that is unique to mammals. It helps to maintain a healthy body temperature for a particular animal in a particular environment. The colors and patterns of hair sometimes help to camoufl age an

animal. Some animals have sensitive, long hairs on their faces. Cat whiskers are one example. Cats’ whiskers help them explore and sense the environment.

FeathersFeathers protect an animal’s body by helping to maintain body temperature. Feathers also enable birds to fl y. Some feathers have rachis or hooks that hold them together, but not all feathers do. Feathers on male birds are often more colorful than on female birds. A peacock

is a good example. You might know other birds that live near you. Some species of birds have short, soft feathers called down. Down does not have a rachis, barbules, or the little hooks found in most feathers. This allows down to stay fl uffy, providing warmth and helping water birds to fl oat. Usually, down covers newborn birds’ bodies, too.

21Lesson 2 How Do Particular Structures Allow Animals to Survive?

Learn Even MoreTail Gland The bodies of water birds, such as ducks and cormorants, release oils that they spread over their feathers. The oils prevent water from soaking their feathers and making the birds heavy. A gland, located in the tail area, produces this oil. Birds cannot fl y with wet feathers. If you watch ducks, you will see that they rub their bills on their tail regions to collect the oily secretion and spread it over their feathers.

HornsAnimals’ horns are made of the same material as hair. Like hair, horns grow continuously. They can be cut without hurting an animal. Animals use their horns to attract mates, to defend themselves against predators, and to be recognized in a group. Male cattle (called bulls), and several animals that live in African savannahs have horns.

22 Life of Animals

2Claws and HoovesClaws and hooves on animals are like your fi ngernails. Hands and legs allow an animal to stand and to handle or hold objects. Their toes and hooves help them balance. In some animals, they create friction with surfaces they move in or on. In ungulates, such as horses, the center grows larger, thicker, and more resilient so it can support the animal’s weight.

ScalesScales protect an animal’s body and help it move. Fish have several types of scales. Sharks and rays, for example, have tiny scales that feel like teeth. Shark skin is very rough. If you look at it under

a microscope, you can see patterns like tiny shark teeth! Shark scales lay back and enable a shark to use less power to swim at higher speeds.

Scales grow continuously and erratically, forming rings, allowing humans to determine the age of the fi sh. Scales are not repaired when they are lost.

23Lesson 2 How Do Particular Structures Allow Animals to Survive?

24

LESSON 3

How Do Habitats Meet an

Organism’s Basic Needs?

What do you know about the habitat where this snake lives?

How do animals live there?

25

Lab ActivityHabitat in a Bag

You are going to make a habitat in a bottle. First, fi ll the bottom of the cut 2 liter bottle with about 1 centimeter of gravel.

Cover the gravel with 2½ centimeters of soil.

Use a pencil or other pointed object to make a shallow furrow through the soil. Put some grass seeds and bean seeds into the furrow and cover them with about ½cm of soil.

Water the soil gently until you see the water begin to wet the gravel.

Place the bottle inside a zippered baggie and seal it. Do you think you will have to keep watering the plant?

Observe your habitat for a few days. Record in your Science Notebook the changes that you notice.

26 Life of Animals

3

1 inch

1/2 inch

27Lesson 3 How Do Habitats Meet an Organism’s Basic Needs?

Learn MoreRainforest EcosystemSome ecosystems have a consistently cold climate, such as the tundra found near the North and South Poles. Others have consistently warm climates, such as those near the equator. Because of their climate, the tropics and rainforests are home to a vast range of animal and plant life. These photographs show a few of the mammals that live in rainforests around the world.

OrangutansOrangutans once lived in many parts of Asia, but now they are endangered. Today, orangutans only live on two islands: Borneo and Sumatra. Orangutans are among the smartest primates. They can often be observed using tools. They spend much of their time high in the trees that grow in the warm climate near the equator.

TapirsTapirs are large mammals that look somewhat like pigs. They live in forest habitats in South and Central America, and in Southeast Asia. Tapirs are related to horses. They have snouts similar to an elephant’s trunk, but much shorter. A tapir can walk underwater in rivers, holding its breath as it fi nds food. Some fi sh have adapted to clean tapirs by eating insects and parasites off of their bodies.

28 Life of Animals

3JaguarsJaguars are the largest type of cat found in the Americas. They range from the Southwestern region of the U.S. to South America. Jaguars are the third largest species of cat; only lions and tigers are bigger. Male jaguars can weigh up to 160kg. Jaguars are carnivores, which means that they only eat meat. Because humans are destroying the forests that they live in, jaguars are considered to be threatened with extinction.

BatsBats are the only mammals that fl y. Many types of bats live in rainforests around the world. There are over 1,000 species of bats, of all different sizes. The smallest are only about 2cm long, while the largest can be over 33cm. Bats do not have good eyesight, but they have good hearing. They use sound waves to navigate as they fl y. Whales and dolphins also use this adaptation, called echolocation, to navigate.

SlothsSloths live in rainforests in Central and South America. They spend their lives in trees, eating mostly leaves and tree buds. Sloths only come down from the trees about once a week. When they move, they move very, very slowly. A sloth’s fur is its own ecosystem. It is often covered with algae, and those algae are home to many types of insects.

29Lesson 3 How Do Habitats Meet an Organism’s Basic Needs?

30

LESSON 4

How Do Organisms Depend on

Their Environments

for Food?How does this rabbit depend on its environment for food?

How might other animals depend on the rabbit?

31

Lab ActivityOwl Pellet Dissection

Observe the owl pellet carefully before you dissect it. In your Science Notebook, represent your observations with a drawing and a written description.

Gently begin to separate the owl pellet.

After the owl pellet is completely separated, observe and describe what you see. What might cause the owl to regurgitate the parts that are in the owl pellet?

Separate all the fur from the bones.

Identify the bones using the bone identifi cation chart and organize them on a piece of paper.

Use glue to attach the bones and other parts to a sheet of paper. Label each piece.

What is the predator-prey relationship between the owl and other animals in its ecosystem? What kind of animals do owls eat? Record these answers in your Science Notebook.

32 Life of Animals

4

Owl

33Lesson 4 How Do Organisms Depend on Their Environments for Food?

Learn MoreHow Do Arctic Animals Get Food?Arctic areas are frozen for much of the year. Vegetation is often limited, or it is buried beneath snow. How do animals living in this extreme environment get the food they need, so they have the energy they need to survive? Many animals eat fi sh, seals, and other ocean wildlife, while others animals seek their prey on land. The following photographs show arctic animals and information about how they get the energy they need to survive.

Arctic wolves are predators. They live in the Canadian Arctic, Alaska, and Greenland. Because their habitat is often covered with ice, these carnivores have to roam large areas to fi nd enough food to survive. Arctic wolves can be found following packs of larger prey animals, such as caribou and muskoxen.

Although all species of bears are omnivores, polar bears live in areas where there is often little or no vegetation. Because of this, they also have to hunt other animals for food. Polar bears have adaptations that help them to be successful in the arctic. They are not fast runners, but polar bears’ white fur lets them blend in with the snow, so they can sneak up on their prey as they hunt on land. Their sharp claws help them to grab fi sh and seals from the ocean. Their large paws allow them to walk over thin ice without falling through. Polar bears spend much of their lives in and around water, so they are strong swimmers. Polar bears are the top predators in many Arctic food chains.

Arctic Wolf

Polar Bear

34 Life of Animals

4Puffins are birds that live in Arctic regions. They are predators. Puffi ns hunt by diving into the ocean to catch fi sh. They can fl ap their wings underwater, swimming quickly as they try to catch their prey. Puffi ns can dive to 60m under water, and they can stay there for a full minute. They are the only birds that carry more than one fi sh in their beaks at a time.

The walrus is one of the largest types of seals. It can be identifi ed by its large tusks and whiskers. Living in Arctic and subarctic areas, walruses have adapted to survive in cold temperatures. They have a thick layer of blubber that keeps them warm. Their fl ippers are adapted to move on ice and in the water. When they hunt, walruses can hold their breath for up to 30 minutes. They can dive down to 80m deep. Walruses forage for bottom-dwelling animals such as clams, shrimp, crabs, and sea cucumbers.

As you can see in the photo, an arctic hare’s fur camoufl ages it, so it can hide from its predators. Hares are adapted to survive in the cold. They can dig deep into the snow, where they create burrows in which they can huddle together to keep warm. Arctic hares are herbivores; they eat only plants. But because vegetation is scarce, they eat any type of plant they can fi nd. They eat all types of shrubs, grasses, trees, and even moss and lichens (a type of fungi and algae). Hares spend a lot of time digging to uncover vegetation buried beneath the snow.

Arctic Hare

Walrus

Puffi n

35Lesson 4 How Do Organisms Depend on Their Environments for Food?

36

LESSON 5

How Are Life Cycles

Dependent on Habitats?

What role does water play in the lives of frogs and alligators?

What would happen to these animals without water?

37

Lab ActivityLife Cycles

Look at the worksheets for the Alligator Life Cycle and Bullfrog Life Cycle. You can see that the photos are not in the correct sequence. Do one of the following: 1) number the photos in the correct order on the page, or 2) cut them out and arrange them in the correct order.

In your Science Notebook, represent the life cycles of the alligator and the bullfrog. Use arrows to show progressions from one stage to the next stage. Label the three stages.

38 Life of Animals

5

Circle any place in the life cycle where one of the animals depends on water. Do alligators and bullfrogs depend on water at the same stage in their life cycles?

Read the Learn More section about the role of water in the life cycles of amphibians and reptiles. As you read, pay attention to the characteristics of these animals that help them to survive in an aquatic environment.

Comparison is an important tool for scientists. They look carefully at what is alike and what is different among species, and they study how those characteristics are important for survival. Compare the physical characteristics of alligators and bullfrogs at each stage in their life cycles. Be as detailed as you can in your explanation of how their similarities and differences are important for survival.

39Lesson 5 How Are Life Cycles Dependent on Habitats?

Learn MoreWater in the Lives of AmphibiansSalamanders, frogs, and toads belong to a group of animals called amphibians. Amphibians live in water during some part of their lives. Adult amphibians live outside the aquatic environment, but they still depend on water for reproduction and protection. Because they depend on water, amphibians live in wetlands, or they live in and around ponds. Amphibians breathe through their lungs and their skin. Their skin must always be wet to enable gases to pass through. Their skin is thin, and often has patterns, like the frog in this photo.

Because most amphibians lay their fertilized eggs in water, they do not need rigid shells. Shells prevent the contents of an egg from drying out,

so eggs laid in water do not need hard shells. Out of the eggs, tadpoles hatch. Tadpoles remain in the water until the metamorphosis stage, when they become adult frogs. Tadpoles look like fi sh with big heads and small tails. They breathe through gills, like fi sh do. During metamorphosis, tadpoles grow legs, lose their tails, and begin to breathe through their lungs and skin.

40 Life of Animals

The Mata-Mata is a carnivorous turtle that is camoufl aged among the dead leaves of rivers and lakes.

Lizard Eggs in a Tree

5 Water in the Lives of ReptilesReptiles need water, but not in the same way that amphibians do. Some species of reptiles live in aquatic environments, but they still need a terrestrial environment (land) to breed. Marine turtles and some tortoises are examples.

Reptiles needs less water because they have specialized eggs, skin, and urine. Their eggs, which are deposited on land, have a leathery shell. The strong shell protects them from drying out. Amphibian skin is waterproof to prevent water from evaporating from their bodies. Their urine is pasty because it has so little water in it.

41Lesson 5 How Are Life Cycles Dependent on Habitats?

42

LESSON 6

How Do Animals

Coexist for Survival?

Within a species, when do animals have specifi c jobs?

How does an animal’s body shape help it to accomplish a specifi c task?

43

Lab ActivitySocial Interaction

With your team, examine the images on these two pages. Discuss what you see in each image. Record your ideas in your Science Notebook.

Based on the animals’ body language, expression, or situation, determine what the group might be trying to accomplish.

Read the Learn More section about ways different groups of animals work together to survive.

Gorillas

44 Life of Animals

6

Meerkats

Dolphins

Bees

People

45Lesson 6 How Do Animals Coexist for Survival?

Learn MoreSocial BehaviorSome species of animals live in large colonies. Individuals interact in different ways and for different purposes within the colony. For example, some form small groups that seek food. Others provide care or defend the members from predators. Some keep the living areas clean. Some work in nurseries, caring for the offspring born in the colony. Bees, ants, termites, mole rats, and wasps are social animals that share these types of traits.

Pack HuntingWolves are the size of larger dogs. They are strong, but a single wolf would not be able to attack a 600-kg moose. To meet their needs for survival, wolves (and other pack animals) hunt in groups. As they learn from one another’s mistakes, they become very strategic hunters. Wolves have developed effective hunting strategies. Some members of the pack chase a large animal until the animal gets tired. The wolves get tired, too. When that happens, other wolves, who are not tired, attack the prey from both sides at the same time.

Wolves

46 Life of Animals

6

Naked Mole Rat

Naked mole rats, a species found in East Africa, live in underground colonies. Their social organization is similar to bees’. Each colony has one queen. About three males are responsible for reproduction. The other rats are workers. They maintain the nest, protect the young, and seek food.

47Lesson 6 How Do Animals Coexist for Survival?

Learn Even MoreInsect SocietiesInsects, such as termites, ants, and some species of bees and wasps, have complex social organizations. No one animal lives independently. Each has a role to play as a part of the colony in which it developed. Individuals commonly have specifi c tasks, such as to obtain food. The physical characteristics of each individual correspond to the functions they have in society.

QueenThe queen is the only female to produce new offspring. She is usually the largest member of the colony. The queen also chooses the site to build a new colony, and begins construction of a new nest.

This image shows the queen bee along with many worker bees working together in the honeycomb.

48 Life of Animals

You can recognize soldier ants by their size and their mandibles.

MalesIn an entire termite colony, there may be just one male. Bees, ants, and wasp colonies might have more, but the males of several species die soon after fertilization.

WorkersThere are more workers than any other kind of insect in a colony. They are not able to reproduce. Their role is to do the work of the colony: maintenance, construction, cleaning, feeding the queen and larvae, caring for eggs, collecting food, and producing honey and royal jelly. In some species, the workers also protect the colony, as in the case of a beehive.

SoldiersAnts and termites have a group who specialize in protecting the colony against predators. Called “soldiers,” these insects have large, powerful jaws and glands that produce substances to sting or smell bad to their enemies. You can recognize soldiers by their size and often by their large mandibles or jaws.

14

49Lesson 6 How Do Animals Coexist for Survival?

50

LESSON 7

What Happens to Animals

When an Ecosystem Changes?

What do you see happening in this image?

How do forest fi res affect the animals that live in this ecosystem?

51

Lab ActivitypH and Acid Rain

Species Survival in Different Levels of Acidity

Fill a cup halfway with water.

Dip one pH test strip into the water. Record the pH level in your Science Notebook.

Predict what will happen to the pH level of the water when lemon juice is added.

Add a spoonful of lemon juice to the water. Test the pH level with another strip. Record the results in your Science Notebook.

Add one more spoonful of lemon juice to the water. Again test the pH level and record it in your Science Notebook.

52 Life of Animals

7

Look at the chart to determine if the water is acidic enough to affect the life of animals. Record your ideas in your Science Notebook.

Add plain water to the cup and test the pH level again. What happens to the pH? Why?

Add a pinch of sodium bicarbonate to the cup of water. What happens to the pH? Add more and see what happens.

Species Survival in Different Levels of Acidity

pH 6.5 pH 6.0 pH 5.5 pH 5.0 pH 4.5 pH 4.0

Trout

Bass

Perch

Frogs

Salamanders

Clams

Crayfi sh

Snails

Mayfl y

53Lesson 7 What Happens to Animals When an Ecosystem Changes?

Learn MoreDeforestationDeforestation has several possible causes. Climate change and acid rain are two environmental factors that can kill many or all of the trees in a region. Human activity causes most deforestation. Sometimes, forests are cut down or burned so the land can be used for new farms, for grazing cattle, or for roads

and buildings. Deforestation has serious consequences for ecosystems. Animals may become extinct; climates can change; fl ood patterns can change, and areas that were once green can become deserts. At this point in human history, over half of Earth’s rainforests have been destroyed. Scientists believe that if the rate of deforestation continues, in twenty more

years, less than 20% of Earth’s original rainforest will remain.

When Columbus came to America, half of the U.S. was forest. By 1850, most of the forests in the east had been cleared. Today, little of the original forest exists. Continued deforestation will mean the extinction of thousands of species of plants and animals.

Some deforestation happens through a method called clear-cutting. In this method, all the trees are removed from a certain area.

54 Life of Animals

7

After a forest is clear-cut, there are not enough natural resources to support most of the animals and other living organisms that may have previously lived there.

55Lesson 7 What Happens to Animals When an Ecosystem Changes?

Learn Even MoreUnplanned DesertsSometimes an ecosystem becomes so unhealthy that neither plants nor animals can survive. Deforestation can lead to deserts forming in areas that were not always deserts, as the land becomes dry and barren.

56 Life of Animals

7

Slash and BurnSlash-and-burn deforestation is a method in which trees are systematically cut and burned. This method of clearing forests and burning wood not only destroys the forest ecosystem but also sends unhealthy gases into the air.

As more of Earth’s forests are cleared, more habitats will be destroyed. Some species will adapt or fi nd new places to live; others will not be able to adapt and will become extinct.

57Lesson 7 What Happens to Animals When an Ecosystem Changes?

58

LESSON 8

How Do Humans

Affect Ecosystems?

How do animals help humans accomplish different tasks?

Can animals survive without humans?

59

Lab ActivityAnimal and Human

Relationships

Examine the images on the Human Animal Relationship cards. Consider the following questions:

● What is the relationship between the animals and humans?

● Who benefi ts from the relationship?

● How might these relationships affect the ecosystem?

● Has the environment been altered?

● Has an animal been taken from its natural surroundings?

Record your ideas in your Science Notebook.

With your group, discuss your ideas about the relationships between animals and humans. After recording your main ideas, prepare to share your findings with the class.

60 Life of Animals

8

61Lesson 8 How Do Humans Affect Ecosystems?

Learn MoreMost animals have life cycles that begin with eggs and progress through stages until they die. All animals have structures and habits that help them grow and survive. Every type of animal has a unique skeletal structure, for example, that is suited to the particular environment in which they live. Some animals have an internal skeleton (called an endoskeleton), and others have an external skeleton or shell (called an exoskeleton).

Animals all have a place in the food chain. The food chain starts with the sun and a producer. A producer must live in a habitat that supports its basic needs. Major changes to an environment can seriously affect animal habitats and change an entire ecosystem. The effects of deforestation can deplete natural resources. This directly affects the number and type of species that can live in what remains of a forest. As one animal dies, others in the food chain are affected. Without that animal as its food, other species will struggle to survive, or they will also die.

Another type of deforestation also leads to changes in an ecosystem. Acid rain can poison the air, land, and water. Deforestation caused by acid rain also changes the animal and plant populations in the ecosystem. If a species cannot adapt, it cannot survive, and that results in species becoming extinct.

Population IncreasesExamine the two photographs on the next page. One shows a farm with a lot of land and food, and very few people. Long ago, few farm machines required gasoline. Gasoline is a fuel produced from petroleum, which is a natural resource. Most families once coexisted with the land, using a minimal amount of the natural resources and producing very little waste. They did not cause vast amounts of pollution to change the environment for the plants and animals that lived there.

62 Life of Animals

8

The image of New York City shows many streets, buildings, and lights. All of these are indicators that a large number of people live in the city. This photo is a sampling of how different animals’ habitats would look in any highly populated area. If more people live in an area, more food,

water, shelter, and energy are needed. This means less space and resources for animals and plants. Instead of producing food for animals, people in urban areas (large cities) use resources to meet their own needs. Resources are needed for transportation. Energy is needed for lights, heating

and cooling, technology, and entertainment. The only wild animals that live in cities are those who adapt to the conditions there. Three animals often found in cities are pigeons, cockroaches, and rats. All of these animals have adaptations that allow them to live close to humans.

A Scene from Farming Practices in the Early 1900s

New York City Midtown Skyline at Dusk

63Lesson 8 How Do Humans Affect Ecosystems?

Learn Even MoreNatural Changes to EcosystemsTemperature, rainfall, tornadoes, and hurricanes are some of the natural factors that can change the balance of an ecosystem. Hurricane Katrina in 2005 is one example. The hurricane was devastating for people, as well as for the ecosystem. Flooding in the city of New Orleans destroyed homes and plants, and killed people as well as animals.

New Orleans Flooded by Hurricane Katrina

64 Life of Animals

8

Resources and EcosystemsPeople use natural resources to live, usually resources from the area near where they live. They cut down trees and clear the land to build houses or plant crops. They change the fl ow of water so it will serve their needs. For example, they redirect water to drain swamp areas or they build dams to control fl owing water. Humans can live almost anywhere. Eventually, they built

railroads, trucks, ships, cars, and airplanes to transport goods long distances. This allowed people to move into places where only animals could survive at one time. To acquire resources, humans dig into the earth for minerals, build roads, drill for oil, and cut trees. The environmental changes as a result of human activity have both positive and negative effects on the plants and animals that live there.

65Lesson 8 How Do Humans Affect Ecosystems?

66

acid rain – rain that contains acid usually derived from burning fossil fuels

adapt – to change to enhance survival in response to changes in the environment

adaptation – a change in a trait that allows a species to meet its basic needs for survival

aquatic environment – surroundings related to water

barbs – part of a feather connected to the rachis

barbules – part of a feather connected to the barbs, containing small hooks

basic needs – the minimum requirements that need to be met so an organism can survive (includes food, water, shelter, air and the ability to reproduce)

carnivore – an animal that eats primarily meat from other animals

climate – the typical weather found in a region

climate change – long-term variation in global weather patterns

colony – group of animals or insects living together in a way that supports the entire group

crustacean – an invertebrate animal with ten or more jointed legs, a hard protective shell, two pairs of antennae, and eyes at the end of stalks

deforestation – the removal of trees from an area

ecosystem – a biological environment of different organisms interacting with each other and the environment

endoskeleton – internal skeleton surrounded by soft tissue, such as muscle and skin

exoskeleton – external skeleton or shell

Glossary

66 Life of Animals

extinct – when a species completely dies out

food chain – a linear group where the fi rst organism is eaten by the second, which is eaten by the next organism, and so on, in the chain

habitat – the place where an organism lives; a place that offers conditions favorable for the development, survival, and reproduction of an organism

herbivore – an animal that eats plants

life cycle – the stages of development for an organism, from an egg to a mature adult

migration – periodic relocation for resources, weather, or a breeding location

omnivore – an animal that eats both meat and plants

predator – an animal that eats other animals in order to survive

prey – an animal hunted by other animals

producer – an organism that produces its own food, usually with energy from the sun

quill – bottom, hollow part of a feather

rachis – main shaft of a feather

resources – food, water, shelter

shelter – a structure living things use to protect themselves from weather and danger

social interaction – an interaction between two or more individuals

survival – the continuation of life or existence

vane – part of the feather than contains barbs and barbules

67Glossary

Life of Animals