HomeOrder MaterialsShort FilmsSome Animals Are More Equal Than Others: Keystone Species and Trophic Cascades
Some Animals Are More Equal Than Others: Keystone Species and Trophic Cascades
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What determines how many species live in a given place? Or how many individuals live in a given habitat? Answers to these basic questions eluded ecologists in the early 1960s. It took bold experiments by Robert Paine and James Estes to establish the importance of keystone species in regulating ecological communities, and to begin to understand the cascades of effects set in motion by their removal. For this short film, the two eminent scientists came together to recount their pioneering experiments and how their findings impact conservation decisions facing us today.
Dedicated to the memory of Robert Paine (1933–2016).
For educational resources that support using this film in the classroom, visit www.BioInteractive.org/keystone

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