Download Limiting Factors

Limiting Factors
Learning Objectives
★ I will explain what limiting factors are
★ I will explain how limiting factors affect
organisms and ecosystems
Biotic Potential
All animals on earth reproduce in some way.
This allows their species to continue on.
Even though all animals reproduce, they all
differ in how many offspring they can
produce
Biotic Potential
The biotic potential of an organism is the
maximum number of offspring that a
species could produce if there were
unlimited resources.
Biotic Potential
There are a few different factors that
regulate the biotic potential of organisms:
1. Birth Potential
2. Capacity for Survival
3. Breeding Frequency
4. Length of Reproductive Life
Birth Potential
This is the maximum number of offspring
per birth (i.e. how many babies something
has).
Ex. Whooping cranes lay 2 eggs per year
but usually only 1 survives so the birth
potential would equal 1
Capacity for Survival
This is the number of offspring that reach
reproductive age.
Ex. Turtles lay tons of eggs at a time but
only a few make it to the ocean and then
even fewer actually live to reproductive age
Breeding Frequency
This is how often an organism
reproduces in a year.
Ex. Elk mate only once a year while mice or
rabbits mate multiple times in a year
Length of Reproductive Life
This is how long in an animal’s life that it
can produce offspring.
Ex. African elephants can reproduce until
they are about 90 years old but can’t start
reproducing until they are 15. So they can
reproduce for approximately 75 years.
Limiting Factors
These factors prevent organisms from
reaching their biotic potential.
Any resource that is short in supply is a
limiting factor (food, water, territory,
pollutants, toxins, etc.)
Limiting Factors
There are abiotic and biotic factors that
affect the growth of a population.
Abiotic: sunlight, temperature, chemical
environment
Biotic: food, predators, disease, competition
for resources
Carrying Capacity
This is the maximum number of
individuals of a species that can be
supported by an ecosystem.
This is determined by food and water
availability, shelter, etc.
Carrying Capacity
This system helps to ensure that one
population isn’t taking over the
ecosystem.
It helps to maintain equilibrium.
Density Dependant Factors
A factor that affects members of a
population because of population density.
Examples: food supply, disease, exotic
species, increased predation, competition
Density Independent Factors
A factor that affects a population regardless
of population density
Examples: flood, fire, pesticides,
destruction of habitat, drought.
Crash Course Video
https://www.youtube.com/watch?
v=RBOsqmBQBQk&index=2&list=PL8dPuu
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