Exploring Keystone Species

This Click & Learn shows that keystone species exist across a variety of ecosystems and can exert their influence in different ways. It highlights 15 different keystone species around the world from a variety of trophic levels and ecological roles — including predators, herbivores, scavengers, and ecosystem engineers. Additional information can be found on this resource’s webpage.

Select “Explore the Map” to show how the species are distributed around the globe. To learn more about a specific species, select its image on the map or landing page.

For implementation ideas, including a worksheet that provides a more structured student experience, refer to the materials on this resource’s webpage.

This resource is optimized for use on desktops, modern tablets, and smartphones. It is supported by the most recent versions of Google Chrome, Firefox, Microsoft Edge, and Safari web browsers.

This resource has been designed, optimized, and/or tested for accessibility compliance (WCAG Level 2.0 AA Success Criteria).

Submit comments, questions, or feedback about this resource via email to: biointeractive@hhmi.org.

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Janiszewski, Pawel, Vladimír Hanzal, and Wojciech Misiukiewicz. “The Eurasian beaver (Castor fiber) as a keystone species — a literature review.” Baltic Forestry 20, 2 (2014): 277–286.

Markandya, Anil, Tim Taylor, Alberto Longo, M.N. Murty, S. Murty, and K. Dhavala. “Counting the cost of vulture decline—An appraisal of the human health and other benefits of vultures in India.” Ecological Economics 67, 2 (2008): 194–204. https://doi.org/10.1016/j.ecolecon.2008.04.020.

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Producer

Mark Nielsen, HHMI

Reviewers

Bridget Conneely, HHMI
Jared Lipworth, HHMI
Laura Bonetta, HHMI

Additional Research, Writing, and Editing

Alex Duckles, HHMI
Aline Waguespack Claytor
Esther Shyu, HHMI

UI/UX Design and Development

kapow, inc.

Videos

Clips from BioInteractive:

• Green world hypothesis (“Purple Sea Star”) from Some Animals Are More Equal than Others: Keystone Species and Trophic Cascades
• Salt marsh experiment (“Blue Crab”) from Trophic Cascades in Salt Marsh Ecosystems
• Termite mound from How Termites Enrich Ecosystems

Flying fox, largemouth bass, and leopard clips from Pond5
All other video clips from Shutterstock

Illustrations

Purple sea star diagrams and sea otter graphs by A3MG

Photographs

Andean condor (“Cougar”) from Pond5
“Cougar Close-up” by Sheila Brown, used under CC0
Lakes (“Largemouth Bass”) by Stephen Carpenter, University of Wisconsin–Madison, WI
Meadows (“Eurasian Beaver”) by Alan Law, University of Stirling, Scotland, UK
“Mountain Lion” by James Maxon, used under CC0
“Sea Otter” by Michael L. Baird, used under CC BY 2.0
Trees in the Serengeti (“Blue Wildebeest”) by Tony Sinclair, University of British Columbia, Canada
All other photographs from iStock/Getty Images Plus

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