Ecological Niches and Keystone Species Flashcards
What is a niche?
The role an organism has and the conditions (abiotic factors) it requires to persist. This includes food sources, feeding activities, spatial habitat, reproductive site and activities and relationships and interactions with other species.
What is a fundamental (potential) niche?
The potential role an organism could fill if there were no competitors, predators or parasites.
What is a realised (actual) niche?
The actual ecological niche a species inhabits.
What is the competitive exclusion principle?
The competitive exclusion principle states that no two species can occupy the same niche in the same environment for an extended period of time. One species will outcompete the other for the most limiting resource (e.g. food).
What is resource partitioning?
The fact that competitive exclusion may be avoided if one or both of the competing species evolves, where they no longer require that limiting factor. E.g. they use a different resource, occupy a different area of the habitat, or feed during a different time of day.
What are keystone species?
A species of relatively low abundance that has a disproportionately large influence over low trophic levels.
Why are keystone species important?
They determine the coexistence of organisms in an area.
What do keystone species niches include?
Highly influential relationships with a number of species in a food web.
What are some examples of limiting factors?
- Food/water
- Nutrients
- Sunlight
- Shelter
- Etc
What are the different types of niche partitioning?
- Spatial niche partitioning
- Dietary niche partitioning
- Niche partitioning by resource height
- Temporal niche partitioning
What is spatial niche partitioning?
Types of animals are in different habitats but the same ecosystem.
What is dietary niche partitioning?
Different species in an ecosystem eat different foods but live in the same area.
What is niche partitioning by resource height?
Different species eat different foods, located at different heights.
What is temporal niche partitioning?
Different species eat different foods at different times after events e.g. rain.
