Vocabulary Flashcards
demography
the statistical study of populations
life tables
provide information about the life history of an organism and the life expectancy of individuals at each age
population size
total number of individuals
population density
number of individuals per unit area
quadrat
wood, plastic, or metal square that is randomly located on the ground and used to count the number of individuals that are in it
mark and recapture
- marking animals caught
- releasing them back into the ecosystem to re-disperse
- new sample is captured after time
- count marker in 2nd sample
- equation
mark and recapture equation
total number (and marked) 1st x total number 2nd / number marked 2nd
species distribution pattern
distribution of individuals within a habitat at a particular point in time
-random
-clumped
-uniform
mortality rate
percentage of surviving individuals dying at a particular age interval
mortality rate equation
number of individuals dying / number of individuals surviving x 1000
survivorship curves
graph of the number of individuals surviving at each age interval vs time
- type |
- type ||
- type |||
type | survivorship curve
chance of death low early, high late
type || survivorship curve
constant entire life
type ||| survivorship curve
chance of death high early, low late
k
carrying capacity
carrying capacity
the max amount of individuals an ecosystem can sustain
r
growth rate of populations
r equation
births - death / population size
exponential growth
growth at which it increases indefinitely ; appears when a population has unlimited resources
j shaped curve growth
exponential growth
death rate
number of organisms that die during an interval
birth rate
number of organisms that are born during an interval
positive r value
population increasing in size
negative r value
population decreasing in size
0 r value
zero population growth
zero population growth
0 r value