population changes Flashcards
Clumped dispersion
Individuals are concentrated
Uniform dispersion
Equally spaced out
Random dispersion
An unpredictable pattern
4 factors that affect population change
- Natality
- mortality
- immigration
- emigration
Open population
Allows things to enter and leave population
Closed population
Does not let things enter or leave population
Exponential growth
Size increase as a fixed rate per time
Environmental resistance
Any factor limiting a populations ability to reach its biotic potential
Gene flow
Transfer of genetic info from one population to another
Density dependant factors
factor that influences a population due to density (disease, predation, food supply)
Density independent factors
A factor that influences a population regardless of the population (fire,flood)
Intra-specific competition
And interaction between the same species as they compete for resources
Inter-specific competition
An interaction between different species as they compete for resources
K selected strategy
- long life
- low birth rate
- low birth number
- nurture their young
- large animal
R selected strategy
- short life
- high birth rate
- high birth numbers
- no nurturing
- small animals
Mimicry
Organisms try to mimic another organism or object
Camouflage
Organs try to blend into background or habitat
Three types of symbiosis
- parasitism
- commensalism
- mutualism
Parasitism
One benefits and the other is harmed
Commensalism
One benefits and the other doesn’t care
Mutualism
Both benefit
Succession
Slow replacement of one community of plants by another
Primary succession
Plants take over an area not previously covered by plants. It is slow due to the lack of nutrients (plants growing through pavement )
Secondary succession
Plants take over an area that was previously covered by plants. It is faster due to availability of nutrients (forest fire)
