Texas TEKS 8.12

8.12 is a TEKS knowledge and skills statement. These are the student expectations under it.

• 8.12.A

  explain how disruptions such as population changes, natural disasters, and human intervention impact the transfer of energy in food webs in ecosystems

• 8.12.B

  describe how primary and secondary ecological succession affect populations and species diversity after ecosystems are disrupted by natural events or human acti...

• 8.12.C

  describe how biodiversity contributes to the stability and sustainability of an ecosystem and the health of the organisms within the ecosystem

01

What Students Need to Do

Students trace how a disruption changes energy movement through a food web. They distinguish primary from secondary succession and explain how biodiversity supports ecosystem stability and organism health.

02

What Mastery Looks Like

Students can predict population changes after an organism is added, removed, or reduced. They can identify the succession type, describe likely species changes, and connect greater biodiversity to ecosystem recovery.

03

Common Misconceptions

Students may think every disaster causes primary succession, even when soil remains. They may think energy disappears when populations change, or confuse biodiversity with the total number of organisms.

04

How to Assess It

Give students a food web and a wildfire scenario where soil remains. Ask them to identify the succession type and explain two effects on energy transfer and biodiversity.

1. 01

   Build a yarn food web, remove one organism card, and mark which feeding links lose or gain available energy.

2. 02

   Write a CER response: How would a wildfire change succession, species diversity, and energy transfer if soil remained?

3. 03

   Sort disruption cards into primary or secondary succession, then race to place pioneer, intermediate, and mature community cards in order.

4. 04

   Compare before-and-after species lists from a restored wetland, then explain how greater biodiversity can improve stability and organism health.

• 5.12

  Organisms and environments. The student describes patterns, cycles, systems, and relationships within environments. The student is expected to:

• 7.12

  Organisms and environments. The student understands that ecosystems are dependent upon the cycling of matter and the flow of energy. The student is expected to:

• 4.12

  Organisms and environments. The student describes patterns, cycles, systems, and relationships within environments. The student is expected to:

• 6.13

  Organisms and environments. The student knows that organisms have an organizational structure and variations can influence survival of populations. The student ...