Keystone Species

Keystone species contribute to the "balance of nature" and biodiversity because if it is removed from a system, the ecosystem may change drastically and healthy ecosystems need a keystone to function.

How do keystone species contribute to the "balance of nature" and biodiversity.

The Yellowstone wolves are a keystone species because they have the ability to influence their prey, their prey influencing the plant and animal species beneath them, and so forth down the chain. If the Yellowstone wolves were to be removed from Yellowstone yet again, they could alter the population, distribution, and behavior of their prey, which impacts the other creatures living there—plant and animal—and in doing so they change the landscape itself.

Using the Yellowstone wolves as an example, explain Keystone species and trophic cascade.

A keystone species is a species that has a disproportionately large effect on its environment compared to its relative abundance. This differs from a foundation species because a foundation species is just usually a primary producer that dominates an ecosystem in abundance and influence.

What is a keystone species and how does it differ from a foundation species?

A trophic cascade occurs when a keystone species is removed from an ecosystem. A trophic cascade involves reciprocal changes in the relative populations of predator and prey through a food chain, which often results in dramatic changes in ecosystem structure and nutrient cycling. They occur when the impact of a predator on its prey affects more than one trophic level. Must occur across a minimum of 3 trophic levels. Can also happen from the bottom up (removal of a producer may affect population sizes in trophic levels above it).

What occurs when a keystone species is removed from an ecosystem? Describe the events of a trophic cascade.