6.6.2(Interactions between populations)

Describe the relationship between a population of predator and the population of its prey

• When the predator population gets bigger, more prey are eaten

• The prey population gets smaller, leaving less food for the predators

• With less food, fewer predators can survive and their populations reduce in size

• With fewer predators, fewer prey are eaten and so the prey population increase again

  • With more prey, the predator population gets bigger and the cycle restarts

State what the predator and prey populations are controlled by

• Negative feedback

Describe when competition in an ecosystem occurs

• It occurs when there is not enough resources to satisfy the needs of all the individuals who are relying on that resource

• So individuals begin to compete for the resource

State what intraspecific and interspecific competition affects in an ecosystem

• Intraspecific population:

  • Affects the population of a species within an ecosystem

• Interspecific population:

  • Affects the population of species within an ecosystem

  • Affects the distribution of species within an ecosystem

State the 2 types of competetion

• Intraspecific

• Interspecific

Describe what intraspecific and interspecific competition show

• Intraspecific - Shows changes in population size over time, same species

• Interspecific - Explains the changes in the population size, extinction, pr evolution of species due to other different species

Describe what is meant by competitive exclusion principle

• It states that 2 species who occupy the same niche cannot coexist in the same environment

Describe how the weaker species change under the competitive exclusion principle

• The weaker species will:

  • Go extinct

  • Leave

    • Adapt to another resource and evolve