Topic 6

Question 1

Phylogenies provide a way to ________ how __________ changes over time.

Answer 1

Phylogenies provide a way to quantify how diversity changes over time.

Question 2

Nested similarities are found among extent/extinct species.

Answer 2

Nested similarities are found among extent (living) species.

Question 3

Historical pattern: recorded by _______.

Answer 3

Historical pattern: recorded by fossils.

Question 4

Phylogeny: history of _______ with _________.

Answer 4

Phylogeny: history of descent with branching.

Question 5

Phylogram: a phylogenetic tree where branch lengths represent an inferred amount of ____________ ____.

Answer 5

Phylogram: a phylogenetic tree where branch lengths represent an inferred amount of evolutionary time.

Question 6

Cladogram: a phylogenetic tree where all branches are of _____ ______.

Answer 6

Cladogram: a phylogenetic tree where all branches are of equal length.

Question 7

What is the difference between a cladogram and a phylogram?

Answer 7

Cladograms only represent relatedness between species while phylograms represent an explicit hypothesis about evolutionary time.

Question 8

Monophyletic: includes/does not include a common ancestor and all of its descendants.

Answer 8

Monophyletic: includes a common ancestor and all of its descendants. (One cut needed)

Question 9

Paraphyletic: Includes a common ancestor and some/all of its descendants.

Answer 9

Paraphyletic: Includes a common ancestor and some of its descendants. (More than one cut needed)

Question 10

Polyphyletic: does/does not include the common ancestor.

Answer 10

Polyphyletic: does not include the common ancestor.

Question 11

Phylogenies use characteristics that vary _______ but not ______ species.

Answer 11

Phylogenies use characteristics that vary between but not within species.

Question 12

What type of characters are typically used to construct phylogenies?

Answer 12

1. morphological
2. chromosomal
3. molecular

Question 13

Evidence of relatedness consists of characters, each with a number of ________ _________ ______.

Answer 13

Evidence of relatedness consists of characters, each with a number of discrete character states.

Question 14

Homologous characters: shared because of ______ ________ with shared ancestral and derived characters.

Answer 14

Homologous characters: shared because of common ancestry with shared ancestral and derived characters.

Question 15

Analogous characters: shared because of __________ _________, share similar __________ or ________ but not ______.

Answer 15

Analogous characters: shared because of convergent evolution, share similar appearance or function but not origin.

Question 16

What is synapomorphy?

Answer 16

Homologies shared by some, but not all species, inherited from a recent common ancestor.

Question 17

What is the Principle of Parsimony and how does it apply to phylogenetic reconstruction?

Answer 17

Principle of Parsimony states that the simplest explanation is often the correct one. This means that the tree with the fewest number of changes is the strongest hypothesis regarding evolutionary relationships.

Question 18

Each __________ or ____ difference in a DNA sequence can act as a _____.

Answer 18

Each nucleotide or gene difference in a DNA sequence can act as a trait.

Question 19

Differences in DNA sequences can evolve by _____ or _________.

Answer 19

Differences in DNA sequences can evolve by drift or selection.

Question 20

Genetic difference: smaller/larger distance = more/less closely related.

Answer 20

Genetic difference: smaller distance = more closely related.

Question 21

Macroevolution: evolution _____ the species level.

Answer 21

Macroevolution: evolution above the species level.

Question 22

What is adaptive radiation?

Answer 22

The rapid evolution of new species occupying new niches.

Question 23

Anagenesis: evolution wherein a species is ______ __________ by a new species.

Answer 23

Anagenesis: evolution wherein a species is wholly replaced by a new species.

Question 24

Cladogenesis: parent species _____ into ___ new species.

Answer 24

Cladogenesis: parent species split into two new species.

Question 25

Graduated evolution: slow and steady, gradual evolution, results in more __________.

Answer 25

Graduated evolution: slow and steady, gradual evolution, results in more anagenesis.

Question 26

Punctuated evolution: rare and rapid events of _________ speciation, results in more _______________.

Answer 26

Punctuated evolution: rare and rapid events of branching speciation, results in more cladogenesis.

Question 27

What are some of the potential causes of graduated evolution?

Answer 27

1. Intense competition, limited number of available niches 2. Small population size 2. High specialization

Question 28

What are some of the potential causes of punctuated evolution?

Answer 28

1. Colonization of a new area 2. Diversification following a mass extinction event 3. Evolution of a new trait

Question 29

Most species tend to fit the ______ ________ _____ wherein

Question 30

Most species tend to fit the ______ ________ _____ wherein an individuals of a species tend to converge towards a single optimal trait rather than diverge into several different forms (_________ __________).

Answer 30

Most species tend to fit the single optimum model wherein an individuals of a species tend to converge towards a single optimal trait rather than diverge into several different forms (divergent adaptation).