BIOL 204 Lecture 3: Chapter 54: Community Ecology
Document Summary
Community: an assemblage of populations of various species living close enough for potential interaction. Example: the carrier crab carries a sea urchin on its back for protection against predators. Community structure refers to the number and relative abundances of species in a habitat. Summarized as positive (+), negative (-), or no effect (0) for each organism. Interspecific competition: (-/- interaction) occurs when species compete for a resource in short supply. >interference competition: one species actively prevents another from accessing a resource. >exploitative competition: species reduce the amount of a resource available to the other by using that resource. The sum of species" use of biotic and abiotic resources is called the species" ecological niche. The more similar the niches or two species, the more intensely species will compete. Strong competition can lead to competitive exclusion, local elimination of a competing species.
