BISC 100 Lecture Notes - Lecture 12: Keystone Species, Ecological Succession, Secondary Succession
8 Mar 2020
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Bisc 100 ecosystem part 2: a keystone species is a species whose impact on its community is much larger than its total mass or abundance indicates, experiments in the 1960s. Were among the first to provide evidence of the keystone species effect and. Demonstrated that a sea star functioned as a keystone species in intertidal zones of the. Washington coast: ecologists have identified other species that play a key role in ecosystem structure. For instance, the decline of sea otters off the western coast of alaska allowed populations of sea urchins, their main prey, to increase. Examples of natural disturbances are storms, fire, floods, and droughts. Small-scale natural disturbances often have positive effects on a biological community. Ecological succession that begins in a virtually lifeless area with no soil is called primary succession . Examples include cooled lava flows and the rubble left by a melting glacier.
