Population Regulation

Created by

Jan Brian

Cards (19)

Population Regulation  
Tendency of a population to decrease in size when it is above a particular value (negative feedback). Increase in size when below that level.
Population Fluctuations  
Density fluctuates due to seasonal changes and annual fluctuations brought by extrinsic and intrinsic factors.
Seasonal Changes 
Controlled by life cycle adaptations to seasonal changes in environmental factors.
Top-Down Approach  
Predator-driven approach where a predator's death leads to the flourishing of other populations.
Bottom-Up Fluctuations 
Resource-driven fluctuations within populations
Pulsing Stable 
Not much fluctuations among populations under seasonal changes.
Mega cyclic 
Fluctuations occur within a span of years.
Irruptive 
Unpredictable fluctuations such as desert blooms.
Intrinsic Factors  
Population's own response to density changes (self-regulation) within the population.
Extrinsic Factors 
Related to a Population's interactions with the environment
Intrinsic Factors
Allee Effect
Crowding Response
Territoriality
Dispersal
Genetic change
Extrinsic Factors
Weather
Human Activity
Resource Availability
Diseases and Parasites
Predation
Mechanisms of Population Regulation
Density Dependent Factors
Density Independent Factors
Density Dependent Factors
Allee Effect
Crowding Response
Territoriality
Competition for Resources
Diseases and Parasites
Density-Independent Factors 
Factors whose influence does not vary as density changes.
Predator-Prey Oscillation 
Populations of predator and prey are co-dependent to each other.
Food Quantity Hypothesis 
The availability of food affects a Population.
Epidemiology-Parasite Load Hypothesis 
Fluctuations due to host-parasite interactions. The lessening of host population would limit reproduction of parasite.
Adreno-pituitary feedback hypothesis 
Stress hormones would limit reproduction due to environmental stress.