01. Ecosystems

Ecosystems: Populations

Outcomes:

  • be able to give an example of an ecosystem.

  • be able to explain the limiting factors that affect the organisms in an ecosystem.

  • give examples of the relationships between living things in an ecosystem.

Activity #1:

You are given a copy of the text below. Read it carefully and highlight in different colours the key vocabulary.

"Imagine a wooded area that contains living things such as deer, owl, frogs, ferns, and pine trees as well as non-living things such as rocks, air, and water. This would be an example of an ecosystem. An ecosystem is all the organisms that live in an area together with the nonliving factors of the environment. Can you think of other ecosystems you’re familiar with? A rainforest, tundra, or desert may come to mind.Ecosystems contain various species of living things. A species is a group of organisms that can mate and produce fertile offspring. All the organisms of the same species that live in the same place at the same time make up a population. Examples of populations would include a school of baitfish in the ocean or all the pine trees in a forest.

Populations of living things live with and share the environment with other populations of living things. For example, the forest contains populations of deer, turtles, mushrooms, and bacteria. These different populations living together make up a community. All of the living things in a community also interact with the nonliving factors in their environment. Plants need soil and oxygen to grow while the animal species need water to drink and rocks and caves to shelter them. Different populations of species living together (animals, plants, bacteria) along with other environmental factors make up ecosystems.

For different populations to survive and reproduce, they must have enough resources to meet their needs. These factors are called limiting factors because they have the power to limit the number of organisms that can survive in one space. Examples of limiting factors are the amount of food available, a water source, light for photosynthesis to occur in plants, and living space to obtain resources and reproduce. There are ways that animals live and function together where they all get what they need with limited competition for food. A niche, for example, is a special role or space an organism uses within the habitat. For example, deer, squirrel, and rabbits can live in the same habitat because they all have their own niche. Deer eat from high trees while rabbits graze on the surrounding grass and squirrels eat acorns. They aren’t competing for food.

Living things within the same ecosystem can have different types of relationships with each other. They can compete with each other for food and only the organisms that can get the resources will survive. Predation is when one animal (a predator) will eat another animal (prey). Predator-prey relationships help maintain balance in an ecosystem so one population doesn’t get too big. A third relationship between species is called symbiosis. Symbiosis is a close relationship between species where they help each other. For example, certain types of birds eat the leftover food from a crocodile’s teeth. The birds get fed while the crocodile’s teeth get a nice cleaning."

Activity #2:

First, cut out the SPECIES, POPULATION, COMMUNITY, & ECOSYSTEM flip flaps. Glue them down under each heading. On the front of each flap, write the definition of each word and under each flap, give an example or draw a picture of an example. Add arrows between them to show their order.

Next, cut out and glue down the LIMITING FACTORS flip flap. On the front of the flaps, name 3 limiting factors in an ecosystem. Under the flap, explain WHY it would be a limiting factor and use examples to support your answer.

Next, cut out and glue down the RELATIONSHIPS flip flap. On the front of each flap, record what each term means. Under each flap, give an example or draw a picture.

Finally, respond to the writing prompt.

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