Question 1

What is the difference between Keystone and Dominant?

Accepted Answer

A dominant species has large effects because it is abundant; a keystone has large effects despite being scarce. If you can predict its influence from its biomass, it isn't a keystone — it's just dominant. That test is what the label was supposed to enforce.

Question 2

How do I know if I mean Keystone Species rather than Dominant?

Accepted Answer

Readers who land here meaning Keystone Species rather than Dominant are usually searching for phrases like “what is a keystone species”, “are wolves a keystone species”, “keystone species examples”.

Aspect	Keystone	Dominant
Abundance	Low	High
Effect	Disproportionate	Proportionate
Predictable from biomass	No	Yes
Test	Remove it	Count it

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Keystone Species

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