What do gray wolves, elephants, and parrotfish have in common? They're all keystone species, which means they have an especially large impact on their habitat. SciShow explores how these animals keep their ecosystems running.

Hosted by: Olivia Gordon

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Sources:

General
http://www.nature.com/scitable/knowledge/library/keystone-species-15786127
http://web.utk.edu/~mnunez/Keystones%20Nunez%20Dimarco.pdf

Wolves
http://www.yellowstonepark.com/wolf-reintroduction-changes-ecosystem/
https://www.youtube.com/watch?v=ysa5OBhXz-Q
https://www.researchgate.net/profile/Mark_Boyce2/publication/228623397_Wolves_Influence_Elk_Movements_behavior_Shapes_a_Trophic_Cascade_in_Yellowstone_National_Park/links/09e41508036f97539e000000.pdf
http://ir.library.oregonstate.edu/xmlui/bitstream/handle/1957/25603/RippleWilliam.Forestry.TrophicCascadesYellowstone.pdf
https://www.nps.gov/yell/learn/nature/elkinfo.htm

Elephants
http://nationalgeographic.org/encyclopedia/keystone-species/
https://www.youtube.com/watch?v=hvsWXyIseS0
http://www.sciencedirect.com/science/article/pii/S1146609X11000154
http://thinkelephants.blogspot.co.uk/
http://jmammal.oxfordjournals.org/content/93/3/698
https://www.sciencenews.org/blog/wild-things/importance-elephant-poop
http://www.livescience.com/5650-frogs-find-home-elephant-dung.html

Parrotfish
http://voices.nationalgeographic.com/2014/07/02/to-save-coral-reefs-start-with-parrotfish/
http://www.icriforum.org/caribbeanreport
https://sustainabledevelopment.un.org/content/documents/1891-Status%20and%20Trends%20of%20Caribbean%20Coral%20Reefs-%201970-2012-2014Caribbean%20Coral%20Reefs%20-%20Status%20Report%201970-2012%20(1).pdf

Image Sources:
https://commons.wikimedia.org/wiki/File:%E3%82%A2%E3%82%B9%E3%83%9A%E3%83%B3%E3%81%AE%E6%9C%A8_Aspen_Trees_(8178058710).jpg
https://commons.wikimedia.org/wiki/File:African_Forest_Elephant.jpg
https://commons.wikimedia.org/wiki/File:Ornate_Pygmy_Frog_(Microhyla_fissipes)_%E9%A3%BE%E7%B4%8B%E5%A7%AC%E8%9B%994.jpg
https://commons.wikimedia.org/wiki/File:Microhyla_rubra.jpg
https://commons.wikimedia.org/wiki/File:Sphaerotheca.jpg
https://commons.wikimedia.org/wiki/File:Scarus_vetula_(queen_parrotfish)_(San_Salvador_Island,_Bahamas)_(15548372734).jpg
https://commons.wikimedia.org/w/index.php?title=Special:Search&limit=20&offset=20&profile=images&search=kudu&searchToken=5a246gj4kb5hz9cghc6ro8bc0#/media/File:Kudu_antelope_.JPG
https://archive.org/details/ScienceNationCatchingACoralKiller