Predators can influence the outcomes of competitive interactions among these species.
Herbivory and Competition
Herbivores can also alter the outcome of competition.
Example: Cedar Creek Long Term Ecological Research Site, established by the National Science Foundation.
This research site provides insights into how herbivory influences competitive dynamics in ecosystems.
Overview of Competition
Discussion on different types of competition in ecosystems.
Not all discussion points are verbal; a video segment is included for deeper understanding.
Video Highlights:
Title: "Survival of the Fittest"
Focus on competition as a fundamental ecological principle where organisms strive to grow and reproduce.
Types of Competition
Species interactions can have varying effects:
Both species benefit (mutualism).
One species benefits, while the other is affected negatively (competition).
Competition is defined as a negative interaction where species struggle for shared resources such as:
Air
Food
Water
Space
Classification of Competition
Interspecific Competition:
Competition between individuals of different species for resources.
Intraspecific Competition:
Competition between individuals of the same species for resources.
Mechanisms of Competition
Exploitation Competition:
Individuals compete by utilizing resources more effectively than others.
Example: Squirrels burying their acorns to prevent theft.
Interference Competition:
Individuals physically exclude others from access to resources.
Example: Lions marking their territory to prevent other predators from accessing their prey.
Niches and Resource Partitioning
Every species plays a unique role in its ecosystem, known as a niche.
Niches are crucial in understanding competition:
According to Gauss's principle (competitive exclusion principle):
In a stable environment, two species using the same resource in the same way cannot coexist indefinitely.
Resource partitioning allows species to use resources differently, enabling coexistence and biodiversity.
Example of Resource Partitioning:
Caribbean lizards inhabit different microhabitats: some in tree canopies and others on tree trunks, allowing them to exploit different resources without direct competition.
Effects of Extreme Competition
Consequences of Intense Competition:
Loss or reduction of competition can lead to population explosions in certain species leading to ecosystem imbalances.
Example: In Yellowstone National Park:
Removal of wolves led to increased populations of deer and elk, causing overgrazing and a decline in vegetation and biodiversity.
Reintroduction of wolves in the 1990s moderated these populations, allowing vegetation and biodiversity to recover.
Importance of Competition
Competition is a vital ecological force influencing:
Species diversity
Ecosystem health
Human activities such as overhunting and habitat destruction can disturb competition and ecological integrity.
Future ecological challenges necessitate an understanding of competition to promote conservation.
Types of Competition (continued)
Interference Competition:
Indirect competition through territory defense, without direct resource consumption.
Common in species that exhibit strong territorial behaviors and favor this strategy due to natural selection.
Apparent Competition:
Involves a third party, such as a predator or parasite, influencing the interaction between two species, complicating direct observations and quantification of competition.
Allelopathy in Competition
Definition of Allelopathy:
A form of interference competition where organisms produce chemicals to inhibit the growth of competitors.
These chemicals serve as weapons against other organisms in their vicinity.
Example of Allelopathy:
Common reed (a widely distributed species) produces varying levels of gallic acid:
Different strains show differing degrees of toxicity, affecting the competition dynamics within their ecosystem, particularly concerning invasive species in North America.