Exam 2: phylogenies

Question 1

The goal of Linnaean taxonomy and the resulting system of scientific nomenclature
(convention for naming organisms) is to

Answer 1

classify biological diversity

Question 2

Which of the following is Carolus Linnaeus (1707–1778) responsible for?

Answer 2

having the insight that organisms can be organized into a hierarchical system of classification without having a theoretical explanation for why these patterns should exist

Question 3

The study of phylogeny rests on our observation of characters of organisms, which may
include all of the following EXCEPT

Answer 3

Linnaean taxonomy

Question 4

Which of the following statements about pedigrees and phylogenies is true?

Answer 4

pedigrees tells us about the ancestry of individuals; phylogenis tells us about the ancestry of populations.

Question 5

What is the difference between cladograms, phylograms, and chronograms?

Answer 5

what branh lenghts represents

Question 6

Charles Darwin inferred the pattern of common ancestry without understanding the
basis for heredity. However, if Darwin’s theory of descent with modification is correct, the

Answer 6

DNA sequence similarity should reflect patterns of common ancestry inferred from other evidence.

Question 7

Based on the phylogenetic tree, which of the following is most closely related to

Answer 7

mammals? turtles

Question 8

Based on the phylogenetic tree, which of the following two groups are most closely
related

Answer 8

birds and crocodilians

Question 9

Based on the figure, which of the following statements is true

Answer 9

fish are not a monophyletic group

Question 10

The relationship between placentals, marsupials, and monotremes as shown in the
figure indicates

Answer 10

uncertainty about the relationships between these groups

Question 11

a paraphyletic group contains

Answer 11

the group’s most recent common ancestor but not all of its descendants.

Question 12

What is the difference between a rooted and unrooted tree?

Answer 12

Direction on a rooted tree indicates the passage of time.

Question 13

Although they serve no known current functions, vestigial traits may persist in some
organisms for all of the following reasons EXCEPT that

Answer 13

natural selection cannot act to eliminate traits

Question 14

Analogous traits are found in two or more species becaus

Answer 14

some evolutionary process (usually natural selection) has independently fashioned similar traits in each species.

Question 15

Homologous traits are found in two or more species because

Answer 15

those species share a common ancestor

Question 16

By mapping a given trait on a phylogenetic tree that we have already constructed using
other data, we can

Answer 16

generate hypotheses about when and how this trait evolved.

Question 17

On a phylogram, what do branch lengths represent

Answer 17

the amount of evolutionary change

Question 18

The phylogeny in the figure shows the relationships of raptors (falcons, owls, hawks,
eagles, and osprey) in relation to other birds. Based on this phylogeny, raptors are

Question 19

Which of the following statements is true based on the phylogeny shown in the figure?

Answer 19

primates are members of the Eutheria and mammalia clades

Question 20

The figure shows a hypothesis for the evolution of visual opsins in tetrapods. At the tips,
each triangle represents a particular visual pigment found in a modern tetrapod. Along
ancestral branches, the hypothesized evolutionary history of these opsins is shown. Which
of the following is true of this evolutionary hypothesis?

Answer 20

Squamate reptiles and birds have maintained the ancestral opsins.

Question 21

What is a polytomy?

Answer 21

a rearrangement of organisms of an evolutionary tree to meet at a common point - it shows uncertainty about how lineages relate to each other.

Question 22

Should analogous traits be used to construct phylogenies?

Answer 22

Analogous structures should NOT be used in establishing phylogenies . Analogous structures evolve as a result of similar selection pressures. These two animals are both burrowing mammals, yet are not closely related.

Question 23

which of the following represents a common ancestor and all of its descendants?

Answer 23

a clade