Biology 1407 Exam test quiz and
answers graded A+
In evolutionary terms, an organism's fitness is measured by its _____. - ANS✅✅Contribution to the
gene pool of the next generation
What is the only evolutionary mechanism that consistently leads to adaptive evolution? -
ANS✅✅Natural selection
Within six months of effectively using methicillin to treat S. aureus infections in a community, all new
infections were caused by MRSA. How can this result best be explained? - ANS✅✅Some drug-
resistant bacteria were present at the start of treatment, and natural selection increased their
frequency.
Soapberry bugs use needlelike "beaks" to feed on seeds within the fruits of various plants. Bugs feed
most successfully when their beak length matches the size of the fruit on which they are feeding. For
25 years, populations of soapberry bugs in central Florida have been feeding on small goldenrain
tree fruits that were introduced to the area, rather than on the larger native balloon vine fruits that
serve as food for other soapberry bug populations. Beak lengths of soapberry bugs are variable, but
the average beak length is shorter in soapberry bug populations that feed on goldenrain tree fruits
than in populations that feed on balloon vine fruits, as shown in the graph. How does natural
selection act on beak length in soapberry bug populations? - ANS✅✅The action of natural
selection on beak length in soapberry bug populations varies with the environment.
Charles Darwin _____. - ANS✅✅Proposed natural selection as the mechanism of evolution
The largest unit within which gene flow can readily occur is a - ANS✅✅Species
Males of different species of the fruit fly Drosophila that live in the same parts of the Hawaiian
Islands have different elaborate courtship rituals. These rituals involve fighting other males and
making stylized movements that attract females. What type of reproductive isolation does this
represent? - ANS✅✅Behavioral isolation
According to the punctuated equilibria model, - ANS✅✅Most new species accumulate their
unique features relatively rapidly as they come into existence, then change little for the rest of their
duration as a species.
,Select the correct statement describing sympatric speciation.
- Sympatric speciation has never been observed in nature.
- Sympatric speciation can occur in a single generation.
- Sympatric speciation is always initiated by geographic isolation of two populations. -
ANS✅✅Sympatric speciation can occur in a single generation.
Which of these is an example of temporal isolation?
- One species performs a specific courtship dance. the other species does not.
- The average weight of the individuals in one species is 45 kg; in the other species the average is 290
kg.
- One is a type of primate, the other is a type of marsupial.
- One species is found only in New York, the other only in London.
- One species is nocturnal, and the other species is not. - ANS✅✅One species is nocturnal, and the
other species is not.
Adaptive radiations can be a direct consequence of four of the following five factors. SELECT THE
EXCEPTION.
- evolutionary innovation
-an adaptive radiation in a group of organisms (such as plants) that another group uses as food
-genetic drift
-colonization of an isolated region that contains suitable habitat and few competitor species
-vacant ecological niches - ANS✅✅Genetic drift
The oldest fossils usually _____. - ANS✅✅Are found in the deepest strata
Which of the following taxonomic categories contains all the others listed here?
, -order
-class
-species
-family
-genus - ANS✅✅Class
Animals that possess homologous structures probably _____. - ANS✅✅Evolved from the same
ancestor
Fossil evidence indicates that some dinosaurs had feathers. If birds are indeed descended from
dinosaurs, feathers are what kind of character? - ANS✅✅Shared ancestral character
To apply parsimony to constructing a phylogenetic tree, - ANS✅✅Choose the tree that represents
the fewest evolutionary changes, in either DNA sequences or morphology.
If you were using cladistics to build a phylogenetic tree of cats, which of the following would be the
best outgroup?
- Domestic cat
- Tiger
- Wolf
- Leopard
- Lion - ANS✅✅Wolf
Phylogeny is the evolutionary history of related groups of organisms. Organisms are grouped into
taxa based on homologous characteristics, shared traits that result from common ancestry. Which
statement is true?
- Homologous structures look the same and serve the same function, but they differ in evolutionary
origin and structure.
- Ancestral traits are always simpler than derived traits.
- The term "monophyletic" refers to a taxon that includes an ancestral species and all of its
descendants. - ANS✅✅The term "monophyletic" refers to a taxon that includes an ancestral
species and all of its descendants.
answers graded A+
In evolutionary terms, an organism's fitness is measured by its _____. - ANS✅✅Contribution to the
gene pool of the next generation
What is the only evolutionary mechanism that consistently leads to adaptive evolution? -
ANS✅✅Natural selection
Within six months of effectively using methicillin to treat S. aureus infections in a community, all new
infections were caused by MRSA. How can this result best be explained? - ANS✅✅Some drug-
resistant bacteria were present at the start of treatment, and natural selection increased their
frequency.
Soapberry bugs use needlelike "beaks" to feed on seeds within the fruits of various plants. Bugs feed
most successfully when their beak length matches the size of the fruit on which they are feeding. For
25 years, populations of soapberry bugs in central Florida have been feeding on small goldenrain
tree fruits that were introduced to the area, rather than on the larger native balloon vine fruits that
serve as food for other soapberry bug populations. Beak lengths of soapberry bugs are variable, but
the average beak length is shorter in soapberry bug populations that feed on goldenrain tree fruits
than in populations that feed on balloon vine fruits, as shown in the graph. How does natural
selection act on beak length in soapberry bug populations? - ANS✅✅The action of natural
selection on beak length in soapberry bug populations varies with the environment.
Charles Darwin _____. - ANS✅✅Proposed natural selection as the mechanism of evolution
The largest unit within which gene flow can readily occur is a - ANS✅✅Species
Males of different species of the fruit fly Drosophila that live in the same parts of the Hawaiian
Islands have different elaborate courtship rituals. These rituals involve fighting other males and
making stylized movements that attract females. What type of reproductive isolation does this
represent? - ANS✅✅Behavioral isolation
According to the punctuated equilibria model, - ANS✅✅Most new species accumulate their
unique features relatively rapidly as they come into existence, then change little for the rest of their
duration as a species.
,Select the correct statement describing sympatric speciation.
- Sympatric speciation has never been observed in nature.
- Sympatric speciation can occur in a single generation.
- Sympatric speciation is always initiated by geographic isolation of two populations. -
ANS✅✅Sympatric speciation can occur in a single generation.
Which of these is an example of temporal isolation?
- One species performs a specific courtship dance. the other species does not.
- The average weight of the individuals in one species is 45 kg; in the other species the average is 290
kg.
- One is a type of primate, the other is a type of marsupial.
- One species is found only in New York, the other only in London.
- One species is nocturnal, and the other species is not. - ANS✅✅One species is nocturnal, and the
other species is not.
Adaptive radiations can be a direct consequence of four of the following five factors. SELECT THE
EXCEPTION.
- evolutionary innovation
-an adaptive radiation in a group of organisms (such as plants) that another group uses as food
-genetic drift
-colonization of an isolated region that contains suitable habitat and few competitor species
-vacant ecological niches - ANS✅✅Genetic drift
The oldest fossils usually _____. - ANS✅✅Are found in the deepest strata
Which of the following taxonomic categories contains all the others listed here?
, -order
-class
-species
-family
-genus - ANS✅✅Class
Animals that possess homologous structures probably _____. - ANS✅✅Evolved from the same
ancestor
Fossil evidence indicates that some dinosaurs had feathers. If birds are indeed descended from
dinosaurs, feathers are what kind of character? - ANS✅✅Shared ancestral character
To apply parsimony to constructing a phylogenetic tree, - ANS✅✅Choose the tree that represents
the fewest evolutionary changes, in either DNA sequences or morphology.
If you were using cladistics to build a phylogenetic tree of cats, which of the following would be the
best outgroup?
- Domestic cat
- Tiger
- Wolf
- Leopard
- Lion - ANS✅✅Wolf
Phylogeny is the evolutionary history of related groups of organisms. Organisms are grouped into
taxa based on homologous characteristics, shared traits that result from common ancestry. Which
statement is true?
- Homologous structures look the same and serve the same function, but they differ in evolutionary
origin and structure.
- Ancestral traits are always simpler than derived traits.
- The term "monophyletic" refers to a taxon that includes an ancestral species and all of its
descendants. - ANS✅✅The term "monophyletic" refers to a taxon that includes an ancestral
species and all of its descendants.
