Key Idea: In all environments, individual organisms that depend on the same resource may compete for that resource when it is limited. Resources that can be limited include food, space, water, shelter, and light.

Students are expected to know that:

  1. Organisms that depend on the same resource compete for that resource when it is limited.
  2. Resources that can be limited for animals include food, space, water, and shelter (including nesting sites).
  3. Resources that can be limited for plants include space, water, and light.
  4. Both plants and animals compete for resources.
  5. Competition may be between individuals of the same species or between individuals of different species.
  6. The scientific use of the term “competition” refers to the attempt of different organisms to obtain the same limited resource, whether or not the organisms interact with each other. In other words, competition for resources does not necessarily imply direct confrontation between organisms, and sometimes competition involves finding or using the resource first.

Boundaries:

  1. Students are not expected to know which resources can be limited for other organisms besides animals and plants.
  2. Students are not expected to know that animals compete for light in some instances.