Keystone Species
A keystone species is one whose effect on its ecosystem is far larger than its abundance would predict — remove it and the community restructures.
Full definition of Keystone Species →:: COMPARE ::
KeystonevsDominant
The short 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.
Side by side
| Aspect | Keystone | Dominant |
|---|---|---|
| Abundance | Low | High |
| Effect | Disproportionate | Proportionate |
| Predictable from biomass | No | Yes |
| Test | Remove it | Count it |
What each one means
Dominant
The contrast above sets out how Dominant differs from Keystone Species on the points that actually matter.