Foundational and Keystone Species
Paragraph 1: The harmony present in any ecological system relies on the inclusion of different types of species, each with a specific role or set of roles. Although to some extent all species contribute in important ways, scientists are now learning about the pivotal parts played by what are being called foundational and keystone species. Interestingly, the latter represent only a small fraction of the overall animal population within an ecosystem while the former can make up a significant portion of it. In both cases, though, their removal often results in massive changes to, if not the complete destruction of, their ecosystems. Efforts to conserve these species are currently based on the new idea that they prevent the start of a domino effect that would, once started, be unstoppable.
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