BIOLOGY 1407 BLINN EXAM 1
QUESTIONS AND ANSWERS
The _______ of a phylogenetic tree represents the common ancestor, the _______
represent places where lineages diverge, and the _______ axis represents time.
(Assume that the tree is oriented as depicted in the textbook.) - Correct Answers -root;
nodes; horizontal
Consider four species of conifers. Species A and B are sister species. Species C and D
are also sister species. The clade containing species A and B is a sister to the clade
containing species C and D. Not counting the root as a node, how many nodes would
be found in a phylogenetic tree of species A, B, C, and D? - Correct Answers -two
Traits in two or more organisms that are similar but not derived from a common
ancestor are called - Correct Answers -homoplastic traits
Unrelated lineages of rodents that moved to islands have increased in size relative to
close relatives that are on the mainland. This increase in size is an example of _______
which is a type of _______. - Correct Answers -convergent evolution; homoplasy
Species A and species B have long wings, whereas species C has short wings. Which
piece of evidence would best support the hypothesis that long wings are a
synapomorphy? - Correct Answers -Fossil evidence showing that the common ancestor
of species A, B, and C had short wings
From a survey of Martian life, three hypothetical species are found. These are
nicknamed krons, furs, and pars. If krons and furs are sister species, the resulting
phylogenetic tree will have 45 homoplasies. If krons and pars are sister species, the
tree will have 52 homoplasies. Krons and pars have red body patches, whereas krons
and furs have striped bodies. Based on the principles of parsimony, krons and _______
are sister species, _______ a synapomorphy. - Correct Answers -furs; and striped
bodies is likely
Some species in a hypothetical family of plants are hermaphrodites, and others have
flowers with separate sexes. What would be most useful in determining which condition
was the derived one? - Correct Answers -finding an outgroup
Four different phylogenetic trees of a group of salamanders have been proposed. Trees
A and B each require 12 homoplasies, but tree A requires 14 synapomorphies and tree
, B requires 13 synapomorphies. Tree C requires 15 homoplasies and 13
synapomorphies. Finally, tree D requires 10 homoplasies and 15 synapomorphies.
According to the principle of parsimony, which tree(s) is/are the most accurate? -
Correct Answers -tree D
The trait that would be least useful in a phylogenetic analysis would be one that -
Correct Answers -is altered easily by a small change in diet
Phylogenetic analysis of HIV and nonhuman SIV demonstrates that HIV is _______ and
SIV is _______. - Correct Answers -polyphyletic; paraphyletic
Studies of female platyfishes, whose male counterparts have a variety of tail shapes,
show that the females prefer male fish with artificial swordlike structures attached to
their tails. This observation is most consistent with the - Correct Answers -sensory
exploitation hypothesis
Males of a species of sparrow sing very rapid songs. Experimental evidence shows that
females of this species prefer these fast songs over slowed-down songs. Which would
be the strongest support for the sensory exploitation hypothesis? - Correct Answers -
Related species have males that do not sing as fast, but the females from these other
species also prefer very fast songs over songs of males from their own species.
Scientists have been able to reconstruct DNA sequences in an ancestral archosaur to
produce an opsin protein. Knowledge of the opsin sequence in the ancestral archosaur
provides clues about the animals' visual capabilities and probable behaviors. Which
conclusion based on their results is false? - Correct Answers -the ancestral trait for this
protein could not be recreated
Which statement about Earth's lithospheric crust is true? - Correct Answers -It is made
up of "plates" that can move by continental drift
Which of the following gases have opposing effects on Earth's climate? - Correct
Answers -carbon dioxide and sulfur dioxide
Which of the following is not considered evidence that large meteors struck Earth in the
past? - Correct Answers -High CO2 levels in the atmosphere in certain eras
Humans and chimpanzees diverged about 6 million years ago. If 20 nucleotide
substitutions have occurred between human and chimpanzee lineages in a sequence of
mitochondrial DNA, and 30 have occurred between humans and gorillas, then,
according to the molecular clock hypothesis, humans and gorillas separated _______
million years ago. - Correct Answers -9
which statement about molecular clocks is true? - Correct Answers -they can give an
average rate of change in an amino acid sequence
QUESTIONS AND ANSWERS
The _______ of a phylogenetic tree represents the common ancestor, the _______
represent places where lineages diverge, and the _______ axis represents time.
(Assume that the tree is oriented as depicted in the textbook.) - Correct Answers -root;
nodes; horizontal
Consider four species of conifers. Species A and B are sister species. Species C and D
are also sister species. The clade containing species A and B is a sister to the clade
containing species C and D. Not counting the root as a node, how many nodes would
be found in a phylogenetic tree of species A, B, C, and D? - Correct Answers -two
Traits in two or more organisms that are similar but not derived from a common
ancestor are called - Correct Answers -homoplastic traits
Unrelated lineages of rodents that moved to islands have increased in size relative to
close relatives that are on the mainland. This increase in size is an example of _______
which is a type of _______. - Correct Answers -convergent evolution; homoplasy
Species A and species B have long wings, whereas species C has short wings. Which
piece of evidence would best support the hypothesis that long wings are a
synapomorphy? - Correct Answers -Fossil evidence showing that the common ancestor
of species A, B, and C had short wings
From a survey of Martian life, three hypothetical species are found. These are
nicknamed krons, furs, and pars. If krons and furs are sister species, the resulting
phylogenetic tree will have 45 homoplasies. If krons and pars are sister species, the
tree will have 52 homoplasies. Krons and pars have red body patches, whereas krons
and furs have striped bodies. Based on the principles of parsimony, krons and _______
are sister species, _______ a synapomorphy. - Correct Answers -furs; and striped
bodies is likely
Some species in a hypothetical family of plants are hermaphrodites, and others have
flowers with separate sexes. What would be most useful in determining which condition
was the derived one? - Correct Answers -finding an outgroup
Four different phylogenetic trees of a group of salamanders have been proposed. Trees
A and B each require 12 homoplasies, but tree A requires 14 synapomorphies and tree
, B requires 13 synapomorphies. Tree C requires 15 homoplasies and 13
synapomorphies. Finally, tree D requires 10 homoplasies and 15 synapomorphies.
According to the principle of parsimony, which tree(s) is/are the most accurate? -
Correct Answers -tree D
The trait that would be least useful in a phylogenetic analysis would be one that -
Correct Answers -is altered easily by a small change in diet
Phylogenetic analysis of HIV and nonhuman SIV demonstrates that HIV is _______ and
SIV is _______. - Correct Answers -polyphyletic; paraphyletic
Studies of female platyfishes, whose male counterparts have a variety of tail shapes,
show that the females prefer male fish with artificial swordlike structures attached to
their tails. This observation is most consistent with the - Correct Answers -sensory
exploitation hypothesis
Males of a species of sparrow sing very rapid songs. Experimental evidence shows that
females of this species prefer these fast songs over slowed-down songs. Which would
be the strongest support for the sensory exploitation hypothesis? - Correct Answers -
Related species have males that do not sing as fast, but the females from these other
species also prefer very fast songs over songs of males from their own species.
Scientists have been able to reconstruct DNA sequences in an ancestral archosaur to
produce an opsin protein. Knowledge of the opsin sequence in the ancestral archosaur
provides clues about the animals' visual capabilities and probable behaviors. Which
conclusion based on their results is false? - Correct Answers -the ancestral trait for this
protein could not be recreated
Which statement about Earth's lithospheric crust is true? - Correct Answers -It is made
up of "plates" that can move by continental drift
Which of the following gases have opposing effects on Earth's climate? - Correct
Answers -carbon dioxide and sulfur dioxide
Which of the following is not considered evidence that large meteors struck Earth in the
past? - Correct Answers -High CO2 levels in the atmosphere in certain eras
Humans and chimpanzees diverged about 6 million years ago. If 20 nucleotide
substitutions have occurred between human and chimpanzee lineages in a sequence of
mitochondrial DNA, and 30 have occurred between humans and gorillas, then,
according to the molecular clock hypothesis, humans and gorillas separated _______
million years ago. - Correct Answers -9
which statement about molecular clocks is true? - Correct Answers -they can give an
average rate of change in an amino acid sequence
