Competition | Biology for JAMB PDF Download

Factors that Bring About Competition

• Limited Resources: When resources such as food, water, territory, mates, or sunlight are limited in an ecosystem, organisms must compete for these resources to survive and reproduce.
• Overpopulation: When a population exceeds the carrying capacity of its environment, competition for limited resources intensifies.
• Niches and Habitats: Different species have specific ecological niches and habitats they occupy. Overlapping niches or habitats lead to competition for resources between species.
• Interactions and Relationships: Organisms compete with each other for survival and reproduction due to their interactions and relationships. This competition can occur within or between species.

Inter and Intra-specific Competition

• Inter-specific Competition: Inter-specific competition refers to competition between different species in an ecosystem. It occurs when species share similar resource requirements and occupy similar niches.
  Examples include:
  i. Lions and hyenas competing for the same prey (such as zebras or wildebeests) in an African savanna.
  ii. Trees competing for sunlight and nutrients in a forest ecosystem.
  iii. Birds competing for nesting sites in a particular area.
• Intra-specific Competition: Intra-specific competition refers to competition between individuals of the same species. It occurs when individuals within a population compete for the same resources, mates, or territories.
  Examples include:
  i. Male elephants competing for dominance and access to females during mating season.
  ii. Plants of the same species competing for water and nutrients in a garden.
  iii. Wolves within a pack competing for leadership roles.

Relationship between Competition and Succession

Competition plays a crucial role in the process of ecological succession, which is the gradual change in species composition and community structure over time. The relationship between competition and succession can be summarized as follows:

• Pioneer Species and Primary Succession: In primary succession, pioneer species are the first organisms to colonize barren habitats. These pioneer species often compete with each other for available resources, such as sunlight and nutrients. The competition helps determine which species are best adapted to the environment and can survive. Over time, as the community develops and matures, more complex species replace the pioneers.
• Climax Communities and Competitive Exclusion: In mature ecosystems or climax communities, competition between species continues but is generally reduced. This is because each species has evolved to occupy specific niches and utilize different resources, reducing direct competition. Competitive exclusion principle states that no two species with identical niches can coexist in the long term.
• Facilitation and Succession: Competition can also drive facilitation during succession. Facilitation occurs when one species modifies the environment in a way that makes it more suitable for other species to establish and grow. This process helps facilitate the transition from one stage of succession to the next.