Ecology (population) - Week 19 Flashcards
Define population:
Group of same species individuals, living in the same location
Define community:
Group of populations of different species in the same location
Define speciation:
The evolutionary process, organisms become better suited to their environment over time
Define ultimate:
Through natural selection, organisms adapted to maximise fitness in their environment
Define ;
direct fittness
Indirect fittness
inclusive fitness
Number of offspring produced
Shared genes with indirect offspring
Sum of both
Define
biotic
abiotic
other organisms
Physicochemical/ non-living, water, wind, temp, light, etc
Define
intra-specific
inter-specific
competition
Competition, predation, parasitism, disease
Define
Response curve
Abiotic features of environment effect how well an organism function
Define
Ecological niche
fundamental niche
Relized niche
Role and position species has in it’s environment, how it meets needs: food, shelter, shag etc, includes all a/biotic factors
In absence of other organisms
In presence of other organisms
What is life history theory?
Pattern and duration of key events in an organisms lifetime that affects the number of offspring produced
What is
Iteroparous
Semelparous
Breeds multiple times throughout life
breeds once
What is
K selected life histories?
R selected life histories?
Crowded environments, strong competition, few offspring, invest in growth and survival over loads of reproduction, whales
Short-lived, exploit habitat/ resources quickly, rapid population growth
What is
Stochastic environment change:
Ephemeral habitats:
Highly unpredictable
Only available in short periods (R species live here)
Define
Abundance
Density
Dispersion
number individuals in population
Number of individuals per unit area/ volume
Pattern of spacing between individuals within population
What are the styles of population distributions?
Aggregated/ clumped: most common, water holes
uniform; evenly spaced/ less competition
random: rare, plants in wind, sea currents etc
What are some factors for changes in abundance/ demographic factors?
Birth + immigrants - death - Emigrants
Population growth rate is exponential when what?
Grow rate slows/ stops when what?
resources are unlimited
Resources depleted, birth rate = death rate
What are some secondary and primary demographic factors and how do they affect population abundance?
Weather, food, shelter, breeding sites, habitat, biotic factors
Birth rate, death rate, im/ emigration
secondary affects primary affecting population abundance
What are some density-independent (not related to pop size) and dependant (directly related to pop size) factors that affect birth/ death rate?
Does density-dependent factors affect all individuals evenly?
Climate extremes, events, fires etc
Competition for resources, disease, predation territory etc
No, the strong survive, the weak die
What is determination and regulation?
precise abundance of individuals reflect combined effects/ factors that affect population, independent and dependant
Tendancy of population to increase when low and decrease when high population level
What is the only thing that can regulate abundance?
Density dependant factors
Which affects K and R type organisms more?
independent/ dependant factors?
K - dependant
R - independant
What is MSY?
Maximum sustainable yield
Largest theoretical yield sustainable harvest over indefinite period
What are the issues with MSY?
No accurate pop size, carry capacity changes, other mortality causes unknown social/ mating strategy
Could lead to collapse of world fisheries
msy heavily misused
