keystone species

[ kēstōn′ ]

A species whose presence and role within an ecosystem has a disproportionate effect on other organisms within the system. A keystone species is often a dominant predator whose removal allows a prey population to explode and often decreases overall diversity. Other kinds of keystone species are those, such as coral or beavers, that significantly alter the habitat around them and thus affect large numbers of other organisms. Compare indicator species.

Nearby words

  1. keysmash,
  2. keystone,
  3. keystone comedy,
  4. keystone joist,
  5. keystone kop,
  6. keystone state,
  7. keystoner,
  8. keystroke,
  9. keyway,
  10. keyword

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.