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You graphed your population survivorship %
over the weekend!
Now we are going to use a different type of
graph paper to make ANOTHER graph, for a
different type of analysis
Semi-log graph paper!!!
 Size
 Density
 Distribution
 Age
structure
 Birth rate
 Death rate
 Population growth rate
 Reproductive strategy
 Describes
the number of
individuals per unit area
 Usually,
larger organisms have
lower population densities
because they require more
resources to survive
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Higher densities make it easier for
organisms to find mates but leads to
competition
◦ They may also be more vulnerable to
predators and disease
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Describes the spatial
distribution of
organisms within an
area
Random
distribution—
individuals located
haphazardly in
space in no
particular pattern
 Uniform
distribution—
individuals are
evenly spaced
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Clumped
distribution—
organisms arranged
according to the
availability of
resources needed to
survive
◦ Most common in
nature
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Describes the relative numbers of
organisms of each age within a population
A population made up mostly of
individuals past reproductive age will
decline over time
A population with many individuals of
reproductive age will increase over time
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+
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Survivorship curves show the likelihood of
death
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Type I survivorship curves have a high death
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Type II survivorship curves have equal rates
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Type III survivorship curves have highest
rate at older ages
of death at all ages
death rates at young ages
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Populations grow when the birth
rate is higher than the death rate
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When a population increases by a fixed
amount each year
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Every population is eventually constrained by
limiting factors
These may include
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Habitat size
Food
Mates
Other resources
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Rises sharply at first but then begins to level
off as the effects of limiting factors become
stronger
1. involves two parents
2. involves sex cells that contain half of the genetic
information (sperm and egg)
3. offspring receive genes from both parents
1. involves only one parent
2. offspring are genetically identical to parent
3. ex) strawberries, bacteria, mushrooms
1.
Males do not give birth
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2.
3.
Females need to have twice as many young as an
asexual organism to maintain the same number
of young in the next generation
Increased change of genetic errors and
defects
Courtship or mating rituals consume time
and energy, can transmit disease, and can
inflict injury on males of some species if
they compete
1.
Provides greater genetic diversity
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2.
Greater chance of reproducing and evolving if
environmental conditions change
Males of some species can gather food for
the female and young and protect them
Over time, most populations exhibit an Sgrowth curve that levels off at a value K. This
value is known as
(A) equilibrium growth rate
(B) exponential growth rate
(C) carrying capacity
(D) logistic growth rate
(E) minimum population density
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R-selected species have a capacity for a high
rate of population increase
◦ Have many small offspring
◦ Little to no parental care or protection
◦ Overcome the massive loss of offspring by
producing so many that a few will survive
◦ Algae, bacteria, rodents, annual plants (dandelions),
and most insects
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R-selected species are
opportunists/generalists
◦ Reproduce and disperse rapidly when
conditions are favorable or when a
disturbance opens up a new habitat
or niche for invasion
◦ Adapted to unstable climate and
environmental conditions
Most r-selected species go through
(A) irregular or irruptive population changes
(B) irruptive or stable population changes
(C) stable or irregular population changes
(D) stable or cyclic population changes
(E) cyclic or irregular population changes
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K-selected species have a lower population
growth rate
◦ Have fewer, larger offspring with long life spans
◦ Later reproductive age
◦ Offspring are born fairly large, mature slowly, and
have high parental care
◦ Most large mammals, birds of prey, large and longlived plants
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K-selected species do well in competitive
conditions when their population size is
near the carrying capacity of their
environment
◦ Specialists
◦ Competitors
◦ Adapted to stable climate and
environmental conditions
Which of the following types of species would
be least susceptible to the fragmentation of
its habitat due to human influences?
(A) generalists
(B) specialists
(C) large predators
(D) K-Selected species
Opportunist species are most commonly
(A) introduced exotics
(B) competitors
(C) K-strategists
(D) r-strategists
(E) none of the above
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
Age structure diagrams provide information
about a country’s
I. growth rate
II. Generational composition
III. Accumulated retirement funds
(A) I only
(B) II only
(C) III only
(D) I and II only
(E) I, II, and III
The best measure of a society’s quality of life is
its
(A) Gross national product
(B) Educational standards
(C) Life expectancy
(D) Infant mortality rate
(E) Fertility rates