What kind of relationships occur among organisms in an ecosystem, and what are the factors that affect their existence?
Alignment to NC Essential Standards
- 8.L.3.1 — Explain how factors such as food, water, shelter and space affect populations in an ecosystem.
- 8.L.3.2 — Summarize the relationships among producers, consumers and decomposers.
By the end of this lesson, students will be able to:
- Explain how biotic and abiotic factors affect organisms in an ecosystem.
- Describe the different types of relationships that occur between organisms in an ecosystem, with emphasis on the predator-prey relationship.
Access students' prior knowledge on the interaction between organisms and their environment by having them discuss in small groups or as a class the introductory questions, “What are some species that migrate? Why do you think they move from one region to another at certain times of the year?” from the UNC-TV Seasonal Science video “Raptor Migration.”
Show the students the UNC-TV Seasonal Science video “Raptor Migration.”
Introduce the concept of the relationships found in ecosystems between the biotic as well as abiotic factors and connect it to raptor migration from the video using a guided turn and talk activity. See the files below to guide students through a 4-square activity.
Students will access the website http://www.mhhe.com/biosci/genbio/virtual_labs/BL_02/BL_02.html to study and analyze how energy moves through five simplified model ecosystems via food webs. Then they can complete the data table and answer the analysis questions provided on the Ecosystem Relationships Explain Activity Sheet.
Students will view the UNC-TV Science video Animals on the Grid and take notes on the following:
- Why is Ziggy referred to as an “example of nature’s cleanup crew?"
- Why can vultures eat materials that would be hazardous and even fatal for most other animal populations?
- How do you think tracking devices can help protect vultures and other birds?
Students will team up with partners to construct and present a full food web and chart of producers, consumers and decomposers, of one of the following ecosystems, using the resources below for guidance. The presentation will include a five-sentence paragraph summarizing the relationships among producers, consumers and decomposers in that ecosystem.
Deciduous Forest — http://www.world-builders.org/lessons/less/biomes/deciduous/decweb.html
Tropical Rainforest — http://tropicalrainforestscience10.weebly.com/food-web.html