Transcript REACH Populations

POPULATION
DYNAMICS
Assessment 1
If a population is growing at a constant rate of 7%
a year, it will double in approximately
A. 5 years
B. 10 years
C. 15 years
D. 20 years
E. 25 years
Assessment 2
A bottom heavy age structure diagram is indicative
of
A. A population at carrying capacity
B. Slow growth
C. Rapid growth
D. Low mortality rate
E. Low natality rate
Assessment 3
The most important factor in determining a
species’ survivorship curve is
A. The carrying capacity of the species’
ecosystem
B. The species’ population growth rate
C. The species’ population size
D. The species’ parental behavior
E. The climate of the species’ ecosystem
Assessment 4
Exponential growth
A. Starts out fast and gradually slows down
B. Is possible to continue unhindered in the
natural world
C. Is characteristic of the human population
D. Is the same as logistic growth
E. Has an S shaped curve
Assessment 5
An increase in ______ tends to correspond
with a decrease in ______.
A. Infant mortality rate; natality rate
B. Average age at marriage; natality rate
C. Cost of raising children; infant
mortality rates
D. Female literacy rates; fertility rate
E. Urbanization; cost of raising children
Assessment 6
Which explains the high birth rate in contrast to
the rapidly declining death rate during
industrialization?
A. The average age of marriage increasing
B. Nations becoming more developed
C. Increases in many areas including
technological and medical innovations
D. Increase in educational and employment
opportunities for women
E. Hard to change social values that place
value on having many children
Assessment 7
K selected species
A. Perform best in unstable
environmental conditions
B. Thrive in competition
C. Spend lots of energy in reproduction
D. Have constant loss survivorship curves
E. Increase most rapidly when far away
from the carrying capacity
Assessment 8
An example of a r-selected species would be
A. Humans
B. Cats
C. Rodents
D. Eagles
E. Sharks
Assessment 9
Clumping patterns occur with vegetation primarily
because
A. Resources are naturally found in pockets
B. They arise naturally from shading and
resource competition
C. Seeds are randomly distributed
D. Plants secrete antagonistic varietal
chemicals
E. Such patterns arise from chance
Assessment 10
What type of population growth is shown
in the country with the diagram to
the right
A. Slow growth
B. Rapid growth
C. Zero growth
D. Negative growth
Assessment 1
If a population is growing at a constant rate of 7%
a year, it will double in approximately
A. 5 years
B. 10 years
C. 15 years
D. 20 years
E. 25 years
Assessment 2
A bottom heavy age structure diagram is indicative
of
A. A population at carrying capacity
B. Slow growth
C. Rapid growth
D. Low mortality rate
E. Low natality rate
Assessment 3
The most important factor in determining a
species’ survivorship curve is
A. The carrying capacity of the species’
ecosystem
B. The species’ population growth rate
C. The species’ population size
D. The species’ parental behavior
E. The climate of the species’ ecosystem
Assessment 4
Exponential growth
A. Starts out fast and gradually slows down
B. Is possible to continue unhindered in the
natural world
C. Is characteristic of the human population
D. Is the same as logistic growth
E. Has an S shaped curve
Assessment 5
An increase in ______ tends to correspond
with a decrease in ______.
A. Infant mortality rate; natality rate
B. Average age at marriage; natality rate
C. Cost of raising children; infant
mortality rates
D. Female literacy rates; fertility rate
E. Urbanization; cost of raising children
Assessment 6
Which explains the high birth rate in contrast to
the rapidly declining death rate during
industrialization?
A. The average age of marriage increasing
B. Nations becoming more developed
C. Increases in many areas including
technological and medical innovations
D. Increase in educational and employment
opportunities for women
E. Hard to change social values that place
value on having many children
Assessment 7
K selected species
A. Perform best in unstable
environmental conditions
B. Thrive in competition
C. Spend lots of energy in reproduction
D. Have constant loss survivorship curves
E. Increase most rapidly when far away
from the carrying capacity
Assessment 8
An example of a r-selected species would be
A. Humans
B. Cats
C. Rodents
D. Eagles
E. Sharks
Assessment 9
Clumping patterns occur with vegetation primarily
because
A. Resources are naturally found in pockets
B. They arise naturally from shading and
resource competition
C. Seeds are randomly distributed
D. Plants secrete antagonistic varietal
chemicals
E. Such patterns arise from chance
Assessment 10
What type of population growth is shown
in the country with the diagram to
the right
A. Slow growth
B. Rapid growth
C. Zero growth
D. Negative growth
Population Distribution
Describes the
spatial distribution
of organisms
within an area
 Random
distribution—
individuals located
haphazardly in
space in no
particular pattern

Population distribution
 Uniform
distribution—
individuals are
evenly spaced
– Each plant may
need a certain
amount of space
for roots
Population distribution

Clumped
distribution—
organisms
arranged according
to the availability
of resources
needed to survive
– Most common in
nature
Rule of 70

Stuck on a population question? Use the
rule of 70!

Years needed to double=70 / growth rate
Practice Question 1

If a population is growth 5% per year,
how long until it doubles?
Practice Question 2

A country has a population of 100 million
and an annual growth rate of 3.5%. If
the growth rate remains constant, what
will the population of this country be in 40
years?
Exponential Growth

When a population increases by a fixed
amount each year
Logistic growth

Rises sharply at first but then begins to
level off as the effects of limiting factors
become stronger
R vs. K selected species
Birth and death rates

Survivorship curves show the likelihood
of death
Male
Female
Old Age
Reproductive
Age
Youth
Age structure diagrams (pyramids)
Male
Female
Rapid Growth
Guatemala
Nigeria
Saudi Arabia
Ages 0-14
Slow Growth
United States
Australia
Canada
Ages 15-44
Zero Growth
Spain
Austria
Greece
Negative Growth
Germany
Bulgaria
Sweden
Ages 45-85+
The Demographic Transition
Stage 2
Transindustrial
Stage 3
Industrial
Stage 4
Postindustrial
High
80
70
Relative population size
Birth rate and death rate
(number per 1,000 per year)
Stage 1
Preindustrial
60
50
Birth rate
40
30
Death rate
20
10
0
Total population
Low
Increasing Growth Very high Decreasing
Low
Zero
growth rate
growth rate
growth rate growth rate growth rate growth rate
Time
Low
Negative
growth rate