1. Population Ecology Notes

2. Population ecology
1. Populations can be described according
to certain characteristics.
- size of population
- spacing (how organisms are arranged in
a given area)
- density – how many individuals there
are in a specific area

4. Population Density
2. The size of a population occupying an
area of a specific size is called
population density
- the more individuals = more dense of a
population
- less individuals = less dense of a
population

7. Limiting Factors
3. Limiting factor – any biotic or abiotic
factor that restricts the number of
individuals in a population
- examples: food, temperature, living
space, other resources
- populations cannot grow uncontrolled
forever
- what affects one population can affect
others living in same area

8. Competition
4. Competition – contest among organisms
to obtain the resources they need to
survive and reproduce
- population density increases = increase in
competition

10. Carrying Capacity
5. Carrying capacity – the largest number of
individuals an environment can support
and maintain for a long period of time
- when this happens – some individual
may not be able to compete, and will die
or have to find another place to live

12. Carrying capacity

13. Biotic Potential
6. Biotic potential – the number of
individuals each female of a population
can produce under the best possible
conditions
- plenty of food and shelter
- ideal weather, no disease or enemies
- populations never reach biotic potential in the
wild

15. 7. Niche and habitat
1. Niche – all of an organism’s relationships with
its environment (both biotic and abiotic factors)
a. Relationships with others, its offspring, time
of day its most active, and where it finds
shelter
b. An organism’s “lifestyle” – how it
contributes to and fits into its environment
2. Habitat – the actual place an organism lives

17. Questions
1. How is habitat and niche different?
2. Give some examples of things that will
limit a population’s growth?
3. What is the carrying capacity of a
population?
4. What are the three characteristics used
to describe populations?