Download Introduction to Population Dynamics

Populations
Introduction to Population Dynamics
I. Populations
A. What is a population? A group of organisms of the same species
that interbreed and live in the same place at the same time.
1.
2.
II. Population Growth
A. How are populations affected by resources available in the
environment?
1. Resources determine how a given population will grow.
B.
1.
2.
3.
a. Populations grow when birth rate + immigration rate (# of
organisms moving into a population) > death rate +
emigration rate (# of organisms moving out of a population)
III. Limiting Factors
A.
1. Resources, nutrients (matter) and energy in short supply, limit
how large a population can grow, therefore resources can be
limiting factors.
B.
1. Density-dependent limiting factors control population size when a
population is large and crowded.
a. examples: competition, predation, parasitism and crowding
2. Density-independent limiting factors control population size
regardless of whether a population is large or small.
a. examples: natural causes such as geothermal activity, extreme
weather
IV. Carrying Capacity & Population Growth
A. Carrying Capacity- the number of individuals in a
population that can be sustained indefinitely in a given
ecosystem.
-very difficult number to specify
B.
C.
D.
1.
2.
A.
B.
C.