26.2 Phylogenies are inferred from morphological and molecular data

Question 1

11) The term ʺhomoplasyʺ is most applicable to which of these features?
A) the legless condition found in various types of extant lizards
B) the 5-digit condition of human hands and bat wings
C) the beta-hemoglobin genes of mice and of humans
D) the fur that covers Australian moles and North American moles
E) the basic skeletal features of dog forelimbs and cat forelimbs

Answer 1

A) the legless condition found in various types of extant lizards

Question 2

12) If, someday, an archaean cell is discovered whose SSU-rRNA sequence is more similar to
that of humans than the sequence of mouse SSU-rRNA is to that of humans, the best
explanation for this apparent discrepancy would be
A) homology.
B) homoplasy.
C) common ancestry.
D) retro-evolution by humans.
E) co-evolution of humans and that archaean.

Answer 2

B) homoplasy.

Question 3

13) The best classification system is that which most closely
A) unites organisms that possess similar morphologies.
B) conforms to traditional, Linnaean taxonomic practices.
C) reflects evolutionary history.
D) corroborates the classification scheme in use at the time of Charles Darwin.
E) reflects the basic separation of prokaryotes from eukaryotes.

Answer 3

C) reflects evolutionary history.

Question 4

14) Which of the following pairs are the best examples of homologous structures?
A) bat wing and human hand
B) owl wing and hornet wing
C) porcupine quill and cactus spine
D) bat forelimb and bird wing
E) Australian mole and North American mole

Answer 4

A) bat wing and human hand

Question 5

15) Some molecular data place the giant panda in the bear family (Ursidae) but place the lesser
panda in the raccoon family (Procyonidae). Consequently, the morphological similarities of
these two species are probably due to
A) inheritance of acquired characteristics.
B) sexual selection.
C) inheritance of shared derived characters.
D) possession of analogous structures.
E) possession of shared primitive characters.

Answer 5

D) possession of analogous structures.

Question 6

16) In angiosperm plants, flower morphology can be very intricate. If a tree, such as a New
Mexico locust, has flowers that share many morphological intricacies with flowers of the
sweet pea vine, then the most likely explanation for these floral similarities is the same
general explanation for the similarities between the
A) dorsal fins of sharks and of dolphins.
B) reduced eyes of Australian moles and North American moles.
C) scales on moth wings and the scales of fish skin.
D) cranial bones of humans and those of chimpanzees.
E) adaptations for flight in birds and adaptations for flight in bats.

Answer 6

D) cranial bones of humans and those of chimpanzees.

Question 7

17) The importance of computers and of computer software to modern cladistics is most closely
linked to advances in
A) light microscopy.
B) radiometric dating.
C) fossil discovery techniques.
D) Linnaean classification.
E) molecular genetics.

Answer 7

E) molecular genetics.

Question 8

18) Which mutation should least require realignment of homologous regions of a gene that is
common to several related species?
A) 3-base insertion
B) 1-base substitution
C) 4-base insertion
D) 1-base deletion
E) 3-base deletion

Answer 8

B) 1-base substitution

Question 9

19) The common ancestors of birds and mammals were very early (stem) reptiles, which almost
certainly possessed 3-chambered hearts (2 atria, 1 ventricle). Birds and mammals, however,
are alike in having 4-chambered hearts (2 atria, 2 ventricles). The 4-chambered hearts of
birds and mammals are best described as
A) structural homologies.
B) vestiges.
C) homoplasies.
D) the result of shared ancestry.
E) molecular homologies.

Answer 9

C) homoplasies.