Transcript File - jj-sct

CAMPBELL
BIOLOGY
TENTH
EDITION
Reece • Urry • Cain • Wasserman • Minorsky • Jackson
24
The Origin of Species
Clicker Questions by
Bryan Jennings
© 2014 Pearson Education, Inc.
Cynotilapia afra, introduced at West Thumbi Island in Lake
Malawi in the 1960s, has split into two genetically distinct
populations, located at the north and south ends of the
island. How can scientists determine whether these
populations are now different species, according to the
biological species concept?
a) See whether the two populations are morphologically
different from each other: coloring, bone structure, and
so on.
b) Determine whether captured individuals from the two
different populations will mate and produce offspring in a
laboratory fish tank.
c) Determine whether individuals from one population
will interbreed with individuals from the other
population when introduced into each other’s native
habitats.
© 2014 Pearson Education, Inc.
Cynotilapia afra, introduced at West Thumbi Island in Lake
Malawi in the 1960s, has split into two genetically distinct
populations, located at the north and south ends of the
island. How can scientists determine whether these
populations are now different species, according to the
biological species concept?
a) See whether the two populations are morphologically
different from each other: coloring, bone structure, and
so on.
b) Determine whether captured individuals from the two
different populations will mate and produce offspring in a
laboratory fish tank.
c) Determine whether individuals from one population
will interbreed with individuals from the other
population when introduced into each other’s native
habitats.
© 2014 Pearson Education, Inc.
Cichlids in Lake Victoria are thought to have diversified
from a relatively few species to 600 species in about
12,000 years (the last time the lake dried up). What is
the best way to test this hypothesis?
a) Examine the fossil record in lake sediments.
b) Look for morphological characteristics shared
among Lake Victoria species that are distinct from
the species present in other lakes.
c) Look for genetic characteristics shared among
Lake Victoria species that are distinct from
species present in other lakes.
d) This is not a testable hypothesis.
© 2014 Pearson Education, Inc.
Cichlids in Lake Victoria are thought to have diversified
from a relatively few species to 600 species in about
12,000 years (the last time the lake dried up). What is
the best way to test this hypothesis?
a) Examine the fossil record in lake sediments.
b) Look for morphological characteristics shared
among Lake Victoria species that are distinct from
the species present in other lakes.
c) Look for genetic characteristics shared among
Lake Victoria species that are distinct from
species present in other lakes.
d) This is not a testable hypothesis.
© 2014 Pearson Education, Inc.
In what type of environment is a scientist most likely to
find examples of ongoing speciation?
a) areas that have a large range of altitudes, such as
mountains and deep valleys
b) areas such as large plains that facilitate migration of
animals
c) extreme physical environments that are marginal for
supporting life
d) areas that are already species-rich
e) areas that have undergone recent environmental
disturbance or change
© 2014 Pearson Education, Inc.
In what type of environment is a scientist most likely to
find examples of ongoing speciation?
a) areas that have a large range of altitudes, such as
mountains and deep valleys
b) areas such as large plains that facilitate migration of
animals
c) extreme physical environments that are marginal for
supporting life
d) areas that are already species-rich
e) areas that have undergone recent environmental
disturbance or change
© 2014 Pearson Education, Inc.
Sea urchins are broadcast spawners: They release
their gametes into the water without courtship. Which of
these reproductive isolation mechanisms is most likely
affecting sea urchins?
a) behavioral isolation or mechanical isolation
b) gametic isolation or temporal isolation
c) habitat isolation
© 2014 Pearson Education, Inc.
Sea urchins are broadcast spawners: They release
their gametes into the water without courtship. Which of
these reproductive isolation mechanisms is most likely
affecting sea urchins?
a) behavioral isolation or mechanical isolation
b) gametic isolation or temporal isolation
c) habitat isolation
© 2014 Pearson Education, Inc.
You spot a sea snake while you are in a boat on the
ocean and remark about how similar it looks to a snake
that lives in central Illinois. However, you know that
they are most likely separate species due to which of
the following reproductive barriers?
a) behavioral isolation
b) gametic isolation
c) ecological/habitat isolation
d) temporal isolation
© 2014 Pearson Education, Inc.
You spot a sea snake while you are in a boat on the
ocean and remark about how similar it looks to a snake
that lives in central Illinois. However, you know that
they are most likely separate species due to which of
the following reproductive barriers?
a) behavioral isolation
b) gametic isolation
c) ecological/habitat isolation
d) temporal isolation
© 2014 Pearson Education, Inc.
The century cactus flowers every 100 years. A similar
cactus flowers every 50 years. If the 50-year cactus
pollen has the correct characteristics to fertilize the
century cactus, which reproductive barrier will most
likely be working against that possibility?
a) behavioral isolation
b) gametic isolation
c) ecological/habitat isolation
d) temporal isolation
© 2014 Pearson Education, Inc.
The century cactus flowers every 100 years. A similar
cactus flowers every 50 years. If the 50-year cactus
pollen has the correct characteristics to fertilize the
century cactus, which reproductive barrier will most
likely be working against that possibility?
a) behavioral isolation
b) gametic isolation
c) ecological/habitat isolation
d) temporal isolation
© 2014 Pearson Education, Inc.
Several species of amphibians are able to read each
other’s mating rituals and understand them, tend to be
fertile at the same time, and are usually similar in size.
However, when they attempt to mate, they never
produce offspring. Which of the following barriers is
most likely the cause of this?
a) behavioral isolation
b) gametic isolation
c) reduced hybrid fertility
d) hybrid breakdown
© 2014 Pearson Education, Inc.
Several species of amphibians are able to read each
other’s mating rituals and understand them, tend to be
fertile at the same time, and are usually similar in size.
However, when they attempt to mate, they never
produce offspring. Which of the following barriers is
most likely the cause of this?
a) behavioral isolation
b) gametic isolation
c) reduced hybrid fertility
d) hybrid breakdown
© 2014 Pearson Education, Inc.
The fossil record shows that species remain constant
for long periods of time, but then speciation episodes
occur rapidly. This is indicative of
a) gradualism.
b) punctuated equilibrium.
c) allopatric speciation.
d) sympatric speciation.
© 2014 Pearson Education, Inc.
The fossil record shows that species remain constant
for long periods of time, but then speciation episodes
occur rapidly. This is indicative of
a) gradualism.
b) punctuated equilibrium.
c) allopatric speciation.
d) sympatric speciation.
© 2014 Pearson Education, Inc.
When differentiating between two species of fish, you
notice that one species stay near the surface and feed
on floating algae, while the other species are bottom
feeders. This is using the
a) morphological species concept.
b) ecological species concept.
c) phylogenetic species concept.
© 2014 Pearson Education, Inc.
When differentiating between two species of fish, you
notice that one species stay near the surface and feed
on floating algae, while the other species are bottom
feeders. This is using the
a) morphological species concept.
b) ecological species concept.
c) phylogenetic species concept.
© 2014 Pearson Education, Inc.
Which of the following is believed to be the primary
reproductive isolation mechanism for causing sympatric
speciation in North American apple maggot flies
(Rhagoletis pomonella)?
a) polyploidy
b) sexual selection
c) phylogenetic species concept
d) habitat differentiation
© 2014 Pearson Education, Inc.
Which of the following is believed to be the primary
reproductive isolation mechanism for causing sympatric
speciation in North American apple maggot flies
(Rhagoletis pomonella)?
a) polyploidy
b) sexual selection
c) phylogenetic species concept
d) habitat differentiation
© 2014 Pearson Education, Inc.
Scientific Skills Exercises
Researchers studied populations of the dusky salamander
(Desmognathus ochrophaeus) living on different mountain
ranges in the southern Appalachian Mountains.
The researchers tested the reproductive isolation of pairs of
salamander populations by leaving one male and one female
together and later checking the females for the presence of
sperm. Four mating combinations were tested for each pair
of populations (A and B)—two within the same population
(female A with male A and female B with male B) and
two between populations (female A with male B and female
B with male A).
© 2014 Pearson Education, Inc.
The proportion of successful matings for each mating
combination was measured. For example, when all the
matings of a particular combination were successful, the
researchers gave it a value of 1; when none of the
matings were successful, they gave it a value of 0. Then
the researchers calculated an index of reproductive
isolation that ranged from 0 (no isolation) to 2 (full
isolation). The reproductive isolation value for two
populations is the sum of the proportion of successful
matings of each type within populations (AA + BB)
minus the sum of the proportion of successful matings
of each type between populations (AB + BA).
© 2014 Pearson Education, Inc.
What hypothesis did the researchers test in this study?
a) Dusky salamanders are undergoing sympatric
speciation.
b) Dusky salamanders are in the process of
speciation.
c) Reproductive isolation increases with
geographic distance between dusky
salamander populations.
© 2014 Pearson Education, Inc.
What hypothesis did the researchers test in this study?
a) Dusky salamanders are undergoing sympatric
speciation.
b) Dusky salamanders are in the process of
speciation.
c) Reproductive isolation increases with
geographic distance between dusky
salamander populations.
© 2014 Pearson Education, Inc.
Identify the independent variable in this study.
a) the reproductive isolation values for pairs of
dusky salamander populations
b) the geographic distance between dusky
salamander populations
c) the mountain ranges that dusky salamander
populations live in
d) the presence of sperm in cloacas of female
dusky salamanders
© 2014 Pearson Education, Inc.
Identify the independent variable in this study.
a) the reproductive isolation values for pairs of
dusky salamander populations
b) the geographic distance between dusky
salamander populations
c) the mountain ranges that dusky salamander
populations live in
d) the presence of sperm in cloacas of female
dusky salamanders
© 2014 Pearson Education, Inc.
Identify the dependent variable in this study.
a) the courtship behaviors of dusky salamander
populations
b) the geographic distance between dusky
salamander populations
c) the presence of sperm in cloacas of female
dusky salamanders
d) the reproductive isolation values for pairs of
dusky salamander populations
© 2014 Pearson Education, Inc.
Identify the dependent variable in this study.
a) the courtship behaviors of dusky salamander
populations
b) the geographic distance between dusky
salamander populations
c) the presence of sperm in cloacas of female
dusky salamanders
d) the reproductive isolation values for pairs of
dusky salamander populations
© 2014 Pearson Education, Inc.
Why did the researchers set up four possible matings
for each pair of populations: female A + male A; female
B + male B; female A + male B; female B + male A?
a) to assess whether males or females determine
mating success
b) to compare the proportion of successful
matings within populations to the proportion of
successful matings between populations
c) to assess whether populations A and B are separate
species
d) to identify the behavioral or morphological features
that contribute to reproductive isolation
© 2014 Pearson Education, Inc.
Why did the researchers set up four possible matings
for each pair of populations: female A + male A; female
B + male B; female A + male B; female B + male A?
a) to assess whether males or females determine
mating success
b) to compare the proportion of successful
matings within populations to the proportion of
successful matings between populations
c) to assess whether populations A and B are separate
species
d) to identify the behavioral or morphological features
that contribute to reproductive isolation
© 2014 Pearson Education, Inc.
The researchers set up 30 trials for each type of mating
between every pair of populations: 30 trials of female A
with male A, 30 trials of female B with male B, 30 trials
of female A with male B, and 30 trials of female B with
male A. Why did the researchers set up 30 trials for
each type of mating?
a) to control variables
b) to provide replication
c) to avoid experimenter bias
d) to provide a control group
© 2014 Pearson Education, Inc.
The researchers set up 30 trials for each type of mating
between every pair of populations: 30 trials of female A
with male A, 30 trials of female B with male B, 30 trials
of female A with male B, and 30 trials of female B with
male A. Why did the researchers set up 30 trials for
each type of mating?
a) to control variables
b) to provide replication
c) to avoid experimenter bias
d) to provide a control group
© 2014 Pearson Education, Inc.
Calculate the value of the reproductive isolation index if
all of the matings within a population were successful
but none of the matings between populations were
successful.
a) 0
b) 1.0
c) 1.5
d) 2.0
© 2014 Pearson Education, Inc.
Calculate the value of the reproductive isolation index if
all of the matings within a population were successful
but none of the matings between populations were
successful.
a) 0
b) 1.0
c) 1.5
d) 2.0
© 2014 Pearson Education, Inc.
Calculate the value of the reproductive isolation index if
salamanders were equally successful in mating with
members of their own population and members of
another population.
a) 0
b) 1.0
c) 1.5
d) 2.0
© 2014 Pearson Education, Inc.
Calculate the value of the reproductive isolation index if
salamanders were equally successful in mating with
members of their own population and members of
another population.
a) 0
b) 1.0
c) 1.5
d) 2.0
© 2014 Pearson Education, Inc.
Review the scatter plot of reproductive isolation value
versus geographic distance for 27 pairs of dusky
salamander populations. How do reproductive isolation
values change with geographic distance among pairs of
dusky salamander populations?
a) Reproductive isolation values decrease with
geographic distance.
b) Reproductive isolation values increase with
geographic distance.
c) Reproductive isolation values
do not change with geographic
distance.
© 2014 Pearson Education, Inc.
Review the scatter plot of reproductive isolation value
versus geographic distance for 27 pairs of dusky
salamander populations. How do reproductive isolation
values change with geographic distance among pairs of
dusky salamander populations?
a) Reproductive isolation values decrease with
geographic distance.
b) Reproductive isolation values increase with
geographic distance.
c) Reproductive isolation values
do not change with geographic
distance.
© 2014 Pearson Education, Inc.
What does the scatter plot suggest about the process
of allopatric speciation?
a) Geographically isolated populations represent
separate species.
b) Reproductive isolation is more likely to occur
as populations become separated by greater
distances.
c) Reproductive isolation of populations leads to
geographic isolation.
d) Geographically isolated
populations are also
reproductively isolated.
© 2014 Pearson Education, Inc.
What does the scatter plot suggest about the process
of allopatric speciation?
a) Geographically isolated populations represent
separate species.
b) Reproductive isolation is more likely to occur
as populations become separated by greater
distances.
c) Reproductive isolation of populations leads to
geographic isolation.
d) Geographically isolated
populations are also
reproductively isolated.
© 2014 Pearson Education, Inc.
Which hypothesis suggests a possible cause of the
relationship shown in the scatter plot?
a) Geographically separated populations of dusky
salamanders gradually diverge, and the divergence
increases with geographic distance.
b) Small populations of dusky salamanders gradually
diverge due to genetic drift.
c) Sympatric populations of dusky salamanders gradually
diverge because they exploit different food sources.
d) The founder effect results in divergence between
geographically separated populations of dusky
salamanders.
© 2014 Pearson Education, Inc.
Which hypothesis suggests a possible cause of the
relationship shown in the scatter plot?
a) Geographically separated populations of dusky
salamanders gradually diverge, and the divergence
increases with geographic distance.
b) Small populations of dusky salamanders gradually
diverge due to genetic drift.
c) Sympatric populations of dusky salamanders gradually
diverge because they exploit different food sources.
d) The founder effect results in divergence between
geographically separated populations of dusky
salamanders.
© 2014 Pearson Education, Inc.