Chapter 53 Flashcards
the number of individuals per unit area or volume
Density
A pattern of spacing among individuals within boundaries of a population
Dispersion
Under what circumstances would ecologists use the mark and recapture method?
When studying individuals who move around
Population density is determined through ____ and ____
Birth and immigration
Population density is determined by losses through
Deaths and emigration
Common patterns of dispersion
Clumped
Uniform
Random
Individuals or the same species born at the same time
Cohort
A plot of the proportion or numbers in a cohort still alive at each age
Survivorship curve
Three types of survivorship curves
See chapter notes
Exponential growth equation
Dn/dt=rmaxN
Exponential growth graph
See chapter notes
The max population size that a particular environment can sustain
Carrying capacity
Equation for logistic population growth
dN/dt=rmaxN(K-N)/K
If a population is very small then (K-N)/K is approximately equal to what?
1
If a population reaches its carrying capacity, then (K-N)/K equals what?
0
Logistic population growth graph
See chapter notes
Individuals may have a more difficult time surviving or reproducing if the population size is too small
Alee effect
The traits that affect an organisms schedule of reproduction and survived
Life history
Single large reproduction event
Semelparity
Repeated reproduction
Iteroperity
What kind of environment favors semelparity
Desert
What type of survivorship curve is likely associated with semelparity?
3
What type of curve is associated with iteroparity?
1
Organisms face trade offs between reproduction and
Survival
Organisms face trade offs between number and
Size
Under what circumstances does an organism face K-selection?
Factors that select for high carrying capacity
Large
Favor offspring with more parental supervision
Density independent causes of death
Drought, stress, fire, etc..
Name four density dependent causes of death
Disease
Predators
Competition for resources
Toxic waste products
Are populations stable over time
No
Predator prey population relationship
See chapter notes
Multiple populations connected by immigration and emigration
Metapopulation
