26.1 Phylogenies show evolutionary relationships

Question 1

1) The legless condition that is observed in several groups of extant reptiles is the result of
A) their common ancestor having been legless.
B) a shared adaptation to an arboreal (living in trees) lifestyle.
C) several instances of the legless condition arising independently of each other.
D) individual lizards adapting to a fossorial (living in burrows) lifestyle during their lifetimes.

Answer 1

C) several instances of the legless condition arising independently of each other.

Question 2

2) The scientific discipline concerned with naming organisms is called
A) taxonomy.
B) cladistics.
C) binomial nomenclature.
D) systematics.
E) phylocode

Answer 2

Answer: A

Question 3

3) The various taxonomic levels (viz, genera, classes, etc.) of the hierarchical classification
system differ from each other on the basis of
A) how widely the organisms assigned to each are distributed throughout the
environment.
B) the body sizes of the organisms assigned to each.
C) their inclusiveness.
D) the relative genome sizes of the organisms assigned to each.
E) morphological characters that are applicable to all organisms.

Answer 3

C) their inclusiveness.

Question 4

4) Which of these illustrates the correct representation of the binomial scientific name for the
African lion?
A) Panthera leo
B) panthera leo
C) Panthera leo
D) Panthera Leo
E) Panthera leo

Answer 4

Answer: E

Question 5

5) A phylogenetic tree that is ʺrootedʺ is one
A) that extends back to the origin of life on Earth.
B) at whose base is located the common ancestor of all taxa depicted on that tree.
C) that illustrates the rampant gene swapping that occurred early in lifeʹs history.
D) that indicates our uncertainty about the evolutionary relationships of the taxa
depicted on the tree.
E) with very few branch points.

Answer 5

Answer: B

Question 6

6) The correct sequence, from the most to the least comprehensive, of the taxonomic levels
listed here is
A) family, phylum, class, kingdom, order, species, and genus.
B) kingdom, phylum, class, order, family, genus, and species.
C) kingdom, phylum, order, class, family, genus, and species.
D) phylum, kingdom, order, class, species, family, and genus.
E) phylum, family, class, order, kingdom, genus, and species.

Answer 6

Answer: B

Question 7

7) The common housefly belongs to all of the following taxa. Assuming you had access to
textbooks or other scientific literature, knowing which of the following should provide you
with the most specific information about the common housefly?
A) order Diptera
B) family Muscidae
C) genus Musca
D) class Hexapoda
E) phylum Arthropoda

Answer 7

C) genus Musca

Question 8

8) If organisms A, B, and C belong to the same class but to different orders and if organisms
D, E, and F belong to the same order but to different families, which of the following pairs
of organisms would be expected to show the greatest degree of structural homology?
A) A and B
B) A and C
C) B and D
D) C and F
E) D and F

Answer 8

E) D and F

Question 9

9) Darwin analogized the effects of evolution as the above-ground portion of a
many-branched tree, with extant species being the tips of the twigs. The common ancestor
of two species is most analogous to which anatomical tree part?
A) a single twig that gets longer with time
B) a node where two twigs diverge
C) a twig that branches with time
D) the trunk
E) neighboring twigs attached to the same stem

Answer 9

B) a node where two twigs diverge

Question 10

10) Dozens of potato varieties exist, differing from each other in potato-tuber size, skin color,
flesh color, and shape. One might construct a classification of potatoes based on these
morphological traits. Which of these criticisms of such a classification scheme is most likely
to come from an adherent of the phylocode method of classification?
A) Flesh color, rather than skin color, is a valid trait to use for classification because it is less susceptible to change with the age of the tuber.
B) Flower color is a better classification criterion, because below-ground tubers can be influenced by minerals in the soil as much as by their genes.
C) A more useful classification would codify potatoes based on the texture and flavor of their flesh, because this is what humans are concerned with.
D) The most accurate phylogenetic code is that of Linnaeus. Classify potatoes based on Linnaean principles; not according to their color.
E) The only biologically valid classification of potato varieties is one that accurately reflects their genetic and evolutionary relatedness.

Answer 10

E) The only biologically valid classification of potato varieties is one that accurately reflects their genetic and evolutionary relatedness.