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.) - Answer-✅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? - Answer-✅two
/.Traits in two or more organisms that are similar but not derived from a common
ancestor are called - Answer-✅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 _______. - Answer-✅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? - Answer-✅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. - Answer-✅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? - Answer-✅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? -
Answer-✅tree D
/.The trait that would be least useful in a phylogenetic analysis would be one that -
Answer-✅is altered easily by a small change in diet
/.Phylogenetic analysis of HIV and nonhuman SIV demonstrates that HIV is _______
and SIV is _______. - Answer-✅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 - Answer-✅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? - Answer-
✅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? - Answer-✅the ancestral trait for this protein
could not be recreated
/.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. - Answer-✅9
/.which statement about molecular clocks is true? - Answer-✅they can give an average
rate of change in an amino acid sequence
/.the lamiaceae is a(n) _____ of ____ - Answer-✅family;plants
/.which statement about biological classification is false - Answer-✅The same binomial
name may be given to two different organisms as long as they are in different phyla.
/.Had Wallace died before sending a letter to Darwin, which circumstance would be
most likely? - Answer-✅darwin would have published his evolutionary theory later than
he did
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.) - Answer-✅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? - Answer-✅two
/.Traits in two or more organisms that are similar but not derived from a common
ancestor are called - Answer-✅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 _______. - Answer-✅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? - Answer-✅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. - Answer-✅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? - Answer-✅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? -
Answer-✅tree D
/.The trait that would be least useful in a phylogenetic analysis would be one that -
Answer-✅is altered easily by a small change in diet
/.Phylogenetic analysis of HIV and nonhuman SIV demonstrates that HIV is _______
and SIV is _______. - Answer-✅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 - Answer-✅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? - Answer-
✅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? - Answer-✅the ancestral trait for this protein
could not be recreated
/.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. - Answer-✅9
/.which statement about molecular clocks is true? - Answer-✅they can give an average
rate of change in an amino acid sequence
/.the lamiaceae is a(n) _____ of ____ - Answer-✅family;plants
/.which statement about biological classification is false - Answer-✅The same binomial
name may be given to two different organisms as long as they are in different phyla.
/.Had Wallace died before sending a letter to Darwin, which circumstance would be
most likely? - Answer-✅darwin would have published his evolutionary theory later than
he did
