GenreGenre Comprehension SkillComprehension Skill Text FeaturesText Features Science ContentScience Content Nonfi ctionNonfi ction Draw ConclusionsDraw Conclusions • Labels• Labels Plants andPlants and • Diagrams• Diagrams AnimalsAnimals • Glossary• Glossary Scott Foresman Science 3.4Scott Foresman Science 3.4 ì<(sk$m)=bdibia<ì<(sk$m)=bdibia<ISBNISBN 0-328-13818-50-328-13818-5 +^-Ä-U-Ä-U+^-Ä-U-Ä-U
Vocabulary What did you learn? carnivore competition 1. How do animals get energy consumer to hunt for food? decay decomposer 2. What scientific term describes what disease happens when grass grows, gets germs eaten by a mouse, and then thatby Donna Wilson herbivore mouse gets eaten by an owl? omnivore predator 3. What kind of animal has caused harm prey to many trees in the United States by producer eating too many of their leaves? 4. In this book, you have read about producers and consumers. Describe how producers and consumers interact. Use examples Picture Credits Every effort has been made to secure permission and provide appropriate credit for photographic material. from the book. The publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions. Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd). 5 (BR) ©Jerry Young/DK Images; 9 (B) Gerry Ellis/Digital Vision; 12 Getty Images; 15 (CL) ”Barrie Watts/DK Images; 5. Draw Conclusions Suppose you 17 (CB) ”Barrie Watts/DK Images; 20 (Bkgd) Getty Images. Scott Foresman/Dorling Kindersley would also like to thank: 13 Stephen Oliver/DK Images. have seen a lot of mice in your Unless otherwise acknowledged, all photographs are the copyright © of Dorling Kindersley, a division of Pearson. backyard. You have also seen hawks hunting them. Suppose that one day ISBN: 0-328-13818-5 you saw far fewer mice and no hawks. Copyright © Pearson Education, Inc. All Rights Reserved. Printed in the United States of America. What might you conclude? This publication is protected by Copyright, and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permission(s), write to Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025. 3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 05
Earth is a very special place. One of the things that makes it special is the way plants and animals live together, or interact. Sometimes they live together in a way that helps one another. Other times, they live together in a way that hurts one another. Plants and animals can also live together in ways that neither help nor hurt one another. Living things interact in many different ways. However, all living things need other living things in order to live. 2 3
How Living Things Sometimes when two animals interact, only Interact one animal will be helped. This happens when a barnacle attaches to a whale. The adult barnacle does not swim on its own. Instead it eats the bits Some animals live together in groups and help of food that flow past as the whale swims. The each other out. When an ant finds some food, it whale is neither hurt nor helped by having the tells other ants where the food is. Together, the barnacle on its body. ants carry the food back to their home. Barnacles Canada geese with goslings often gather with other mother geese and their goslings. One or two of the mothers will watch over the goslings, while the rest of the mother geese go hunting for food. Animals who live in herds may form a tight circle for protection against bad weather or an enemy. Horses caught in a snowstorm will Sometimes plants and put their heads together in a circle for warmth. animals work together to Often, older horses will push the younger horses help each other. Fruit into the center of the circle for added protection. bats help pollinate certain fruit trees in tropical rain forests. The trees get pollinated and the bats get a meal. 4 5
Living Things Get Energy For plants to be able to grow, bloom, or make seeds, they must have energy. In order for animals to be able to build homes and search for food, they must have energy. Green plants are the only living things that can make their own food. They do this by taking energy from the Sun. Green plants are able to make their own food. This makes them producers. All other living things get energy from the foods they eat. This makes them consumers. Consumers get their energy by eating green plants, or by eating animals that have eaten plants. 6 7
Carnivores, Animals that eat only plants are called Herbivores, herbivores. Goats, horses, and rabbits are herbivores. Some animals eat both plants and And Omnivores other animals. These animals are known as omnivores. Chimpanzees are omnivores. They eat insects, It can take a long time for the energy in a fruits, seeds, and many plant to get to an animal. This is because not all other things. animals eat plants. Animals that eat only meat are called carnivores. You already know about many kinds of carnivores. Tigers, eagles, and mountain lions are carnivores. 8 9
Follow the Energy Marsh hawks are carnivores. They eat rabbits. If a marsh hawk catches and eats a rabbit, it You might have questions about how will get energy from the rabbit. Now think carnivores get their energy from green plants. The back to where the rabbit got its energy. Do you answers are found by looking at a food chain. remember? It was in the clover that the rabbit ate. Energy moves from producers to consumers in a The marsh hawk gets energy from both the rabbit food chain. and the clover. Think of a clover plant growing in a field. The clover plant is green. It makes its own food energy from sunlight. The clover is a producer. Rabbits are herbivores. They eat the clover. By eating the clover rabbits take in energy from the plant. Rabbits are consumers. Rabbit Clover Hawk 10 11
Food Chains There can be more than one food chain in one place. In a field where clover grows, All living things belong to a food chain. Food grass might also grow. Mice eat the grass. chains start with a producer, such as clover. At Owls eat the mice. In this food chain, grass the end of each food chain is a consumer, such as is the producer. The mice and the owls are the marsh hawk. consumers. Owls are predators. They hunt Most food chains have predators and prey. the mice, which are the prey. A predator is an animal that hunts for its food. Another food chain could start when a Prey is the animal that is hunted. The marsh plant’s leaves are eaten by a deer. That deer hawk is a predator, and the rabbit is its prey. could become prey for a bobcat. 12 13
Food Webs One food chain cannot show all the plants and animals that pass on energy, even in a small place. Plants and animals might be eaten by more than one thing. Food webs show what happens when food chains cross. Look at the food web on the right. You read that marsh hawks eat rabbits. They can also eat mice. Owls can eat rabbits. Bobcats can eat deer, rabbits, mice, and even hawks! Food webs show interactions between many living things in an environment. 14 15
How Food Webs What would happen if one part of a food End and Change chain disappeared? For example, suppose a lot of mice were killed or died. The barn owls and marsh hawks might not have enough food. That It may seem like the food web that we just might cause the hawks and owls to go hungry. described ends with the bobcat. However, people If they became hungry enough, they might be sometimes hunt top predators such as bobcats. forced to move to a different place. Other times, accidents, disease, or natural disasters may also kill animals such as bobcats. If that happens, scavengers such as bugs, crows, and coyotes will eat the bobcat. A scavenger is an animal that eats garbage or dead animals. Vultures feeding on a dead sheep 16 17
How Living Things Sometimes the competition between living Compete things is not for food but for space. New homes may be built where animals used to live. Because of this, people may find deer in their backyards If the barn owls and the marsh hawks eating garden plants and bushes. both wanted to find mice, they would be in Many years ago, a plant called kudzu was competition for the mice. In this case, two brought to the United States. After a few different kinds of predators are in competition years the kudzu started growing all over trees for food. Usually, the stronger and faster and bushes. It began to cover and choke out predator will succeed. other plants. The kudzu was too successful at competing with other plants for space to grow. Raccoons eat garbage in the city. 18 19
Environments Tornadoes, hurricanes, floods, droughts, Change volcanic eruptions, and fires are all natural events that can change environments. These natural events sound bad, but they can also bring some Environments can be changed by more than good changes to the environments they affect. just plants competing for space. Animals or Tornadoes and hurricanes blow down many natural events can also change an environment. trees. Many living things grow on these trees. If The gypsy moth is an animal that has changed a tree gets blown over and dies, it will soon be the environment in many parts of the United covered with decomposers. A decomposer is a States. This insect’s larvae eat the leaves of many living thing that breaks down waste and things kinds of trees. When gypsy moth caterpillars eat that have died. The decomposers help the dead too many leaves off too many trees, birds lose tree to decay, or rot. After the tree decays, it their homes. Gypsy moth larvae can eat enough becomes part of the soil again. Other trees leaves to cause some trees to die. need the fertile soil from the dead tree so they can grow. 20 21
A Healthy In addition to good food, people need clean Environment for air and water, shelter, and a clean environment. In order to stay healthy, people also need to People exercise. You can get exercise by working, playing sports, or playing outside. People must also keep themselves clean so People are at the top of many food chains and they don’t get sick. It is important to wash your food webs. We are consumers of both plants and hands before eating so diseases are not spread. animals. Most people in the United States do A disease is a sickness. Germs can cause disease. not grow or catch their own food. They go to a A germ is a very small living thing or particle grocery store to buy it. It is important for people that can make you sick. to eat lots of fruits, vegetables, dairy products, People should also take nuts, whole grains, and fish in order to get the good care of the world vitamins and minerals needed for good health. around them. They can help keep the air and water clean to protect all living things. 22 23
GlossaryVocabulary What did you learn? carnivore competition 1. How do animals get energy carnivore a consumer that eats only to hunt for food? consumer animals and not plants competitiondecay when two or more living things decomposer 2. What scientific term describes what need the same resource happens when grass grows, gets consumerdisease a living thing that eats food germs eaten by a mouse, and then that decayherbivore rotting that returns certain mouse gets eaten by an owl? materials to the soil omnivore decomposerpredator a living thing that breaks down 3. What kind of animal has caused harm prey waste and things that have died to many trees in the United States by diseaseproducer something that causes a living eating too many of their leaves? thing to become ill or sick germs very small living things or 4. In this book, particles that cause diseases you have read about producers and herbivore a consumer that only eats plants consumers. Describe how producers and not animals and consumers interact. Use examples Picture Credits Every effort has been made to secure permission and provide appropriate credit for photographic material. from the book. The publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions.omnivore a consumer that eats both plants Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd).and animals 5 (BR) ©Jerry Young/DK Images; 9 (B) Gerry Ellis/Digital Vision; 12 Getty Images; 15 (CL) ”Barrie Watts/DK Images; 5. Draw Conclusions Suppose you 17 (CB) ”Barrie Watts/DK Images; 20 (Bkgd) Getty Images.predator a consumer that hunts another Scott Foresman/Dorling Kindersley would also like to thank: 13 Stephen Oliver/DK Images.animal for food have seen a lot of mice in your Unless otherwise acknowledged, all photographs are the copyright © of Dorling Kindersley, a division of Pearson. prey an animal that is hunted by backyard. You have also seen hawks others as food hunting them. Suppose that one day ISBN: 0-328-13818-5producer a living thing that makes its you saw far fewer mice and no hawks. Copyright © Pearson Education, Inc. All Rights Reserved. Printed in the United States of America.own food What might you conclude? This publication is protected by Copyright, and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permission(s), write to Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025. 3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 0524
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