Population Growth: Density-Independent vs. Density-Dependent

Density-Independent Growth

Population growth unaffected by population density.

Exponential Growth

Population increases rapidly without resource limitations.

Carrying Capacity (K)

Maximum population size an environment can sustain.

Growth Rate (r)

Per capita growth rate at any time.

Logistic Growth

Growth pattern that slows as resources become limited.

dN/dt

Rate of change in population size over time.

Nt

Population size after t time units.

N0

Initial population size at time zero.

e

Base of natural logarithms, approximately 2.718.

rmax

Maximum possible growth rate under ideal conditions.

Colonization

Establishment of a species in a new habitat.

Recolonization

Return of a species after a disturbance.

Density-Dependent Growth

Population growth influenced by population density.

Biotic Interactions

Interactions among living organisms affecting growth.

Competition

Struggle between organisms for limited resources.

Predation

One organism feeds on another, impacting population.

Disease

Pathogens affecting population health and size.

Waste

Accumulation of byproducts affecting population dynamics.

Stress-Mediated Behavior

Behavioral changes due to high population density.

Environmental Changes

Alterations in habitat affecting population size.

Intrinsic Responses

Behavioral adaptations to changes in population density.

Rabbits in Australia

Example of rapid population growth and control.

Myxoma Virus

Biological control method for rabbit population.

Immunocontraception

Experimental method to control population growth.