Unit 2: Population Dynamics Flashcards
What can population growth models be used for?
To approximate and predict the growth of populations
Carrying capacity can change and vary over time and space as resources do. True or False?
True
What is Density-Dependent Regulation?
regulation of population that is influenced by population density, such as crowding effects (biotic factors)
How is density-dependent regulated?
As Density increases, Intraspecific Competition increases, and Average Fitness decreases
What is Density-Independent Regulation?
regulation of population by factors that operate independent of population density, such as forest fires (abiotic factors)
How is density-independent regulated?
abiotic factors can influence mortality regardless of density
How are metapopulations connected?
By immigration and emigration
What is Metapopulation dynamics?
change in the population of populations
Why are populations in Metapopulations different?
populations are different because subpopulations are exchanging alleles
What can restore or establish populations again?
Migrations
What are are significant predators of patch extinction?
- small population size go extinct quicker
- small size of neighboring population
- low resource abundance
- low heterozygosity (genetic variance)
Why is heterozygosity needed for subpopulations to survive?
the higher the heterozygosity score, the higher genetic variance, which is needed for natural selection and in order to adapt to selective pressure
Who studies or discovered the overall balance between populations extinctions and re-colonizations?
Ilkka Hanski
Given enough time, each populations within a meta population is expected to go extinct. True or False?
True
In order to keep balance, as populations are expected to go extinct within a meta population, how is this balanced?
By migration establishing population, so a stable metapopulation size is maintained
How is meta population size stability threatened?
By factors that decrease meta population connectivity, such as migration barriers or environment changes
What causes population cycles?
Interspecific Interactions:
- host-parasite
- predator-prey dynamic
- competition with other species
As growth rate declines in recent years, population is _________.
still growing
Where is the largest population found?
Chine & India
What are the stages of Age Structure models?
stage 1: rapid growth - will have growth in the future
stage 2: slow growth - will have growth in the future
stage 3: stable - population will stay relatively stable in the future
stage 4: population is expected to decline
populations that _______ K have severe intraspecific competition.
“overshoot”
Rapid growth can continue indefinitely. True or False?
False, rapid growth CANNOT continue indefinitely.
Technological advances have increased K, and global growth is slowing. True or False?
True
What is Age Structure?
proportion of population members at specific age ranges
