Materials

  • CCB Science pages 110 - 117

Standards

Objectives

  • Identify laws of ecology

  • Give examples of environmental disruptions

  • Explain the consequences of disruptions

Key Concept

  • A disruption is a change that greatly alters an environment. Disruptions transform environments. In some cases, one ecosystem can temporarily or permanently replace another. In other cases, an ecosystem can become degraded, making it unfit for living things. Still other ecosystems are destroyed altogether.

Vocabulary

Tier 2 degradation
destruction
destruction
fragmentation
threatened
Tier 3 abiotic
biodiversity
biotic
invasive species

Evidence-Based Reading

  • Repeated Reading: Ask students to read aloud with you as you read ‘Introduced Species as a Disruption’ (beginning on page 112) several times. Tell students to pay special attention to how the punctuation marks, introductory terms such as sometimes and however, and introductory phrases that signify time-order sequence all affect the way you read. Emphasize accuracy and phrasing until the group reading sounds smooth and consistent.

21st Century Skill

  • Media Literacy: Have students read the text and then share how they find reliable media sources. Ask students to give factors that indicate whether a website or resource is trustworthy. Invite students to explain why being media literate is important to their work and their roles as citizens.

Writing Practice

  • Invite students to share their explanations for ways governments can use biodiversity measures to make decisions. Encourage students to discuss how the measures may or may not influence decision making.

Before Lesson

Determine students’ readiness by engaging them in a discussion about what keeps an ecosystem healthy. Write different scenarios on note cards: mouse population in a field ecosystem grows too large; a wetland undergoes a dry period; a mountain ecosystem has too many predators; a desert ecosystem’s cactus plants die off; and so on. Gather students into groups and give each group a note card. Ask students to read their scenarios and describe how equilibrium might be restored.

Background

Remind students that an ecosystem includes both living and nonliving factors. Point out that in an ecosystem, organisms interact with one another and with their physical and chemical environment. Organisms depend on the stable functions of each other and the water, gases, and chemicals that cycle through the ecosystem. Invite volunteers to describe the living and nonliving elements of an ecosystem they have visited or would like to visit.

Guided Practice

  • The Laws of Ecology
  • Responding to Change
    • Fire and Floods as Disruptions
    • Introduced Species as a Disruption
    • Habitat Loss as a Disruptive Force

Core Skill

Determine Meaning: Ask students to think of their favorite sport or hobby. Encourage them to give examples of words that are unique to those activities, such as foot fault and stoppage time in soccer. Explain that most areas of interest and study have unique vocabulary associated with them. Read the text aloud and give students time to find and mark words on the first three pages of the lesson that use specialized words. Recall the word parts and meanings you have already studied to help define certain words. Remind students to mark other words as they continue reading.

Cite Textual Evidence: Give students time to read the text and complete the activity. Encourage students to share specific examples of text evidence that supports the IUCN’s conclusion.

Extension

Use a Graphic Organizer: Gather students into small groups. Ask students to reread Commoner’s laws of ecology presented on page 110 and explain them in their own words. Have students make a four-column chart with a column for each law. Then have students draw or write an example of each law in the chart.

Collect and Display Data: Organize students into small groups. Have them use print and online media to find examples and non-examples of disruption as it relates to ecosystems. Have students organize their research into tables and encourage them to share their work.

Lesson Review