GED Science TestLife ScienceMedium
A group of scientists is studying a remote island ecosystem. They observe that a new invasive plant species has rapidly spread, outcompeting native plants for resources like sunlight and nutrients. This has led to a decline in native herbivore populations and an overall decrease in the island's biodiversity. This scenario best illustrates which ecological concept?
- ACommensalism
- BMutualism
- CSuccession
- DCompetitive exclusion
Show answer & explanationAnswer & explanation
Correct answer: D. Competitive exclusion
Competitive exclusion occurs when two species compete for the same limited resources, and one species is more efficient at utilizing those resources, leading to the decline or elimination of the other. The invasive plant outcompeting native plants for sunlight and nutrients exemplifies this principle.
Why the other options are wrong
- A. Commensalism is a relationship where one organism benefits and the other is unaffected.
- B. Mutualism is a relationship where both organisms benefit.
- C. Succession is the gradual process of change in species composition over time in an ecosystem.
Competitive Exclusion Principle
The principle that two species competing for the same limited resources cannot coexist indefinitely, and one will eventually outcompete and eliminate the other.
- Occurs when niches overlap significantly.
- Leads to the exclusion of one competitor.
- Can reduce biodiversity.
Memory trick: Interactions: Competition, Mutualism, Predation, Commensalism, Parasitism, Exclusion is Competition's end.