EEB 3408W Chapter Notes - Chapter 14: Omnivore, Character Displacement, Rodent

• School: UMN
• Department: Ecology, Evolution, and Behav
• Course: EEB 3408W
• Professor: Cavender- Bares, Jeannine

Document Summary

Pairwise interactions studied so far are idealized. Pairs of competitors or predators and prey do not interact in isolation. With many species, the formulas would become increasingly complex. Experimental tests are also limited to relatively small number of species. Number of potential interactions rise steeply as more are introduced. A 2 species system means 3 treatments. Imagine 3 species interactions a b & c. Net effect of a on b includes: Direct component - increase in a causes decrease in b. Indirect component - increase in a causes decrease in c which causes increase on b. Made time budgets of foraging activity and showed species specialization on different parts of the tree. Used time budgets to estimate overlap of species. More overlap meant more direct competitive interactions. Net interaction between 2 species was mutualistic even though they appeared to be direct competitors. Not directly interacting but both interact with a predator ro parasite in common.