Biology 2483A Lecture Notes - Lecture 15: Trophic Cascade, Keystone Species, Quadrat
3 Nov 2017
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Document Summary
Communities are groups of interacting species that occur together at the same time and place. Species diversity and species composition are important descriptors of community structure. Communities are groups of interacting species that occur together at the same time and place a) Could be physical (community in mountain, dessert, lake etc ) Could be biological (tropical forest, coral reef, meadow etc ) b) Defining the members of a community - all or a subset? i) ii) Impossible to find all because we don"t know if it exists or if its too tiny to see. Tend to work with subsets and which one depends on the question theyre asking. Guild: a group of species that use similar resources. These species play a similar role or function within the community. Primary reason it"s a pyramid is related to its energy. At each tropic level, 90% of the energy is used for metabolism or radiated as heat.
