Explain how living things are dependent upon other living and nonliving things for survival. 

• Explain what happens to an organism when its food supply, access to water, shelter or space (niche / habitat) is changed.
• Identify similarities and differences between living organisms, ranging from single-celled to multi-cellular organisms through the use of microscopes, video, and other media.

Determine the circumstances that cause humans to identify an organism as a pest.