Ecology

• Population


  group of individuals from a single species living in same general area
• Population Ecology


  Study of populations in relation to their environment
• Density


  measure of individuals living in a specific area to understand how crowded/sparse a population is
• Dispersion


  Spacing of individuals
• What types of dispersion are there?

  clumped, uniform, randomly dispersed
• Life Table


  Age-specific summary - survival pattern of a population
• Heroparity


  produce offspring repeatedly
• R-strategists 


  large number of offspring = only some will grow and reproduce
• K-strategists


  small number of offspring = lavish resources spent on one/few individuals
• What does dN represent?

  change in numbers
• What does dt represent?

  change in time
• what does r represent?

  reproductive rate
• what does N represent?

  number
• What is the formula for exponential growth?

  dN/dt = rN
• What is Exponential growth?

  under ideal conditions, the rate of reproduction is at its maximum
• What is the formula for Carrying Capacity?

  dN/dt = rmaxN
• What is Carrying Capacity?

  Maximum population size the environment can support
• Why is there a Carrying Capacity?

  Exponential Growth Rate can't go on forever
• What is the Logistic Model?

  expression reduces per capita rate of increase as N increases
• What is the Logistic Model formula?

  dN/dt = rmaxN (K-N)/K
• What are population dynamics?

  biotic and abiotic interactions create population size variation
• What is the boom-and-bust cycle?


  expansion (boom) and contraction (bust)
• How to define a community?

  assemblage of populations of various species that interact
• How do communities interact?

  competition, predation, mimicry, herbivory, parasitism, mutualism
• What is the Competitive Exclusion Principle?

  two species cannot coexist in the same place
• What is competition?


  species competing for short-supply resources which can lead to elimination of competing species
• What is an ecological niche?

  competition over resources between other species
• What is a fundamental Niche?

  Potential niche a species could occupy
• What is a realised niche?

  actual living conditions
• What is character displacement?

  two competing species in the same environment develop divergent traits to reduce competition
• What is predation?


  one species benefits, the other doesn't. Predator kills the prey.
• What are behavioural defences?

  self-defense, hiding, alarm calls, fleeing
• What is mimicry?


  mimicking other species
• What is Batesian Mimicry?


  Harmless species mimics a harmful one
• What is Mullerian Mimicry


  unpalatable species resemble eachother
• What is herbivory?


  consumption of plants
• What is parasitism?


  attache to host in which it harms and derives its nourishment
• What is mutualism?


  Both species benefit
• What is a dominant species?

  most competitive species in exploiting resources
• What is a keystone species?

  A species that has a disproportionately large impact on its environment relative to its abundance.