Different species often depend on one another. David Gonzales describes the remarkable relationship of the Clark's nutcracker and the whitebark pine, to illustrate the interdependency known as symbiosis.
Symbiosis is only one type of interaction between different species; two other possibilities are parasitism and commensalism. Define each of these phenomena, locate examples of each in the natural world, and create a visual display that organizes your findings. Additionally, try to think of examples in each case where one of the species involved isHomo sapiens.
In July 2011, the U.S. Fish and Wildlife Service cautioned that the Whitebark Pine would soon be extinct without protection. (The agency did not subsequently list the tree as endangered, or begin a protection program, because they say they lack the funding and staff to do so.) What are the threats to the Whitebark Pine? Find out more about this tree species, and explore how its potential demise would affect the other organisms in its habitat.
Are there tree species that are threatened in your area? Check with your state’s forest service, your local Cooperative Extension office, and/or local environmental groups. What could your community do to help?