MS - LS2.A (D) - Predation in Ecosystems - FINAL (WND 2/5/2014)

Module: Predation in Ecosystems

DCI: LS2.A (D) Similarly, predatory interactions may reduce the number of organisms or eliminate whole populations of organisms. Mutually beneficial interactions, in contrast, may become so interdependent that each organisms requires the other for survival. Although the species involved in these competitive, predatory, and mutually beneficial interactions vary across ecosystems, the patterns of interactions of organisms with their environments, both living and nonliving, are shared.

PE: MS-LS2-2 Construct an explanation that predicts patterns of interactions among organisms across multiple ecosystems.

[Clarification Statement: Emphasis is on predicting consistent patterns of interactions in different ecosystems in terms of the relationships among and between organisms and abiotic components of ecosystems. Examples of types of interactions could include competitive, predatory, and mutually beneficial.]

The ideas in this standard are: 

- predatory interactions may reduce the number or organisms

- predatory interactions may eliminate whole populations of organisms

- some interactions between organisms are mutually beneficial, so that populations may become interdependent and require each other for survival

- although species in these competitive, predatory, and mutually beneficial interactions vary across ecosystems, the patterns of interactions of organisms are shared. 

The PE suggests that students need to have a deeper understanding of predation within an ecosystem than what we typically cover on a MC assessment.  Typically, we just address the effects of predation on a population of organisms, and how both the predator species and the prey species are impacted.  This, however, asks students to look across ecosystems for patterns, or similarities, in how these interactions affect communities.