Population Dynamics Flashcards
dispersal does what?
can increase or decrease population densities
who disperses?
expanding populations, those affected by climate change, stream organisms migrating up or down stream, immigrating (increase pops) and emigrating (decrease pops)
metapopulation
a group of subpopulations
- ongoing dispersal can join numerous sub populations to forms a meta population
subpopulation
a part of a larger population with which it sustains a limited exchange of individuals through emigration and immigration
are all populations continuously distributed?
no, cam be clustered in subpopulations or metapopulations
survivorship curve
summarises the pattern of survival in a population and has three types
- is made from life tables
cohort life table
using data from a cohort of similar ages individuals
statistic life table
uses data of age and death of a large number of individuals or the age distribution of a population
type I survivorship curve
low morality of young, high morality of old
type II
constant morality through life
type III
high mortality of young and lower mortality of old
age distributions
the age distribution of a population reflects its history of survival, reproduction and potential for future growth
- survival: age distribution reflects periods of high and low survival
- reproduction: periods of high and low reproduction (fluctuate with environment)
- if the population is replacing itself or in decline
R0
net reproductive rate
the lifetime average number of female offspring left by an individual female in a population and is the sum of lx x mx
lambda
calculated as a ratio of population sizes at two successive points in time
T
generation time
