Unit 4 Lesson 1 What Are Populations, Habitats, and Niches? Copyright Houghton Mifflin Harcourt Publishing Company

Transcription

1 Unit 4 Lesson 1 What Are Populations, Habitats, and Niches?

2 Question 1

3 Who Lives Where? ( living & non living)

4 Who Lives Where? All living and nonliving things in an area and their interactions make up an ecosystem. An ecosystem can be as large as a lake or as small as the area under a rock. Ecosystems are found everywhere organisms live and interact in water or on land.

5 Video!!!

6 Who Lives Where?

7 Who Lives Where? Coral reefs

8 Who Lives Where? Savannas, rain forest, swamps

9 Who Lives Where? Coral reefs, savannas, rain forests, and swamps are all different ecosystems. There are polar ecosystems, too. All parts of an ecosystem are connected and depend on each other. For example, the soil and the temperature determine which plants grow in an ecosystem. The types of animals within an ecosystem depend on the plants there.

10 Who Lives Where? Polar ecosystems are very cold and dry. The Organisms that live in these ecosystems have adaptations to survive the cold weather.

11 Question 2

12 Who Lives Where? Wetlands, such as swamps, have pools of water that cover land. The organisms that live in these ecosystems have adaptations, too. Each ecosystem has plants and animals with adaptations that help them survive.

13 Who Lives Where? Organisms are not evenly distributed among the different ecosystems. Nearly two-thirds of all plants live in tropical rain forests, while few plants grow in polar ecosystems. Within a large ecosystem, there are smaller ecosystems. In the ocean ecosystem, the coral reef ecosystem contains many different organisms.

14 Nearby Neighbors All the people who live in the same neighborhood are part of a community. All the grasses, shrubs elephants, zebras, and other organisms in a savanna are a community. A community is made up of all the organisms that live in the same place.

15 Nearby Neighbors

16 Nearby Neighbors Natural and human activities, such fires and development, change communities over time. During the dry season on the savanna, water is scarce, wildfires are common, and many animals die. During the rainy season grasses, shrubs, and trees grow back quickly. Food and water are plentiful, and the animal populations grow.

17 Nearby Neighbors A population is a group made up of the same type of individuals in an ecosystem.

18 Nearby Neighbors Antelopes and elephants might live in the same community. However, antelopes make up one population, and elephants make up another.

19 Nearby Neighbors Populations can change due to natural causes. For example, if there is not enough food, some animals will not survive.

20 Nearby Neighbors

21 Activity

22 A Place of One s Own All organisms have the same basic needs. However, these needs may be satisfied in different ways. A habitat is the physical part of an ecosystem that meets the needs of an organism. Organisms find food and shelter in their habitats.

23 A Place of One s Own Every organism in a habitat has a role, or niche. The way an organism interacts with a habitat and gets food and shelter are part of its niche. Every organism has body parts that help carry out its niche, such as a duck s webbed feet and oily feathers to swim and stay warm.

24 A Place of One s Own Some animals, such as frogs, change niches during their lifetimes. At first, tadpoles breathe through gills and eat algae. Then, as adults, frogs breathe with lungs and eat insects.

25 A Place of One s Own Organisms compete for resources when their niches overlap. For example, crowded plants may compete for sunlight and for room to grow.

26 Question 3

27 Question 4

28 A Place of One s Own Tadpoles and mosquito larvae compete for algae in a pond.

29 A Place of One s Own

30 Question 5

31 Question 6

32 Producers, consumers and decomposers.

33 Dinner Time! Any living thing that makes its own food is called a producer. Trees and algae are types of producers. Animals cannot make their own food. However, they do need energy. An animal that eats plants or other animals to get energy is called a consumer.

34 Dinner Time! When an organism dies, mold and bacteria break down the remains. A living thing that breaks down wastes and the remains of plants and animals for energy is a decomposer. Mold, mushrooms, and yeasts are types of fungi. Fungi and bacteria are the main types of decomposers.

35 Doing the Dirty Work Decomposers play important roles. They help recycle materials in ecosystems. When an organism dies, fungi and bacteria produce chemicals that help to break down and absorb nutrients from dead organisms and wastes. As decomposers feed, they release useful materials into the ground for plants to use.

36 Doing the Dirty Work Decomposers can also be helpful for people. Yeast is used in baking to make bread rise. Bacteria add taste and texture to milk, producing sour cream and cheese. Decomposers can also help break down human-made pollution, such as oil spills.

37 Question 7

38 Question 1

39 Question 2

40 Question 3

41 Dinner Time! Too much competition For example, if there are too many rabbits, they will not have enough clover to eat. Some will die, and the rabbit population will decrease. Fewer rabbits would allow more plants to grow back. However, fewer rabbits also means less food for the animals that eat rabbits.

42 Wrap up Question 4

43 Wrap up Question 5