Population Ecology

GROWTH MODELSBIDE modelChange in population size over a specific time period

Births + Immigration – Death – Emigration = pop size

Exponential growth

GROWTH MODELS

GROWTH MODELS

What are the assumptions for an exponential growth model?Is this realistic?

GROWTH MODELS

There is a limit to the number of organisms a habitat can support.

Carrying capacity (K)Logistic growth

LOGISTIC GROWTH PRACTICE

Starting population size of 10

= 1.0 (per individual per year)

Carrying capacity = 1,500

Record data for 12 years.

Create a line graph showing the population growth.

GROWTH MODELS

Logistic growth in the real world…

GROWTH MODELS

LIMITING FACTORS

Density dependent

When factors directly affect birth and

death rates.

LIMITING FACTORSDensity dependent prey/predator relationship

DISPERSIONInfluences growth of populations

Influenced by limiting factors (especially density-dependent)

DISPERSION

AGE STRUCTURES

AGE STRUCTURES http://

www.prb.org/Multimedia/Video/2013/population-structure-engage-short.aspx

http://grist.org/population/2011-09-25-7-billion-in-7-minutes-science-magazine-explains-it-all-video/