Transcript CHANGES IN POPULATION SIZE

CHANGES IN
POPULATION SIZE
Population can change in size when new members join
the population or when members leave the population.
BIRTH RATE:
The number of births in a population in a
certain amount of time.
DEATH RATE:
The number of deaths in a population in a
certain amount of time.
Population Size
CHANGES IN
POPULATION SIZE
Population
If birth rate > death rate =
increases
Population
If death rate > birth rate =
decreases
If death rate = birth rate =
Population
Stays the
same
POPULATION DENSITY
- The number of individuals in
a specific area.
What is the formula to calculate
population density?
Number of individuals
_____________
Population Density =
Unit Area
Calculate the population density of flamingos.
Population
Density
10 flamingos
___________
=
= 1.25
8 square meters
Flamingos/
square meter
Calculate the population density of flamingos.
Population
Density
20 flamingos
= ___________ = 2.5 Flamingos/
Square meter
8 square meters
Immigration & Emigration
• Latin root: “Migrare” means “to move”
What do you think the prefixes mean??
Im- “in”
E- “out”
Why might a population move in or out
of a habitat??
The largest population an area can
capacity
support is called its carrying
____________.
The carrying capacity of a population
is determined by limiting factors.
Limiting factor: An environmental factor
that causes a population
to decrease.
food
water space
weather conditions