Biology / Unit 14 Bio 3677 short lesson, about 20 seconds
Keystone Species
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The idea
A keystone species exerts a community-wide effect disproportionate to its abundance, so that its removal collapses community structure other species depend on.
In practice
Removing sea otters lets urchin populations explode and consume kelp forests that had sheltered dozens of other species.
Where people slip
A keystone species is defined by disproportionate impact, not by being the community's most abundant or largest member.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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