Chapter 23

Question 1

what is systematics?

Answer 1

the study of evolutionary relationships

Question 2

What can you construct with systematics?

Answer 2

an evolutionary tree, or phyologeny

Question 3

What is phyologeny?

Answer 3

the evolutionary history of an organism, including which species are closely related and in what order related species evolved

Question 4

With a branching diagram depicting evolutionary relationships, what causes all species to be related in branching?

Answer 4

Descent modification

Question 5

True or false: Evolution can occur very rapidly or very slowly

Answer 5

True

Question 6

True or False: evolution is not always divergent

Answer 6

True, it can also be convergent

Question 7

What is evolutionary reversal?

Answer 7

the process in which a species ca re-evolve the characteristics of an ancestral species

Question 8

What does it mean if a trait is ancestral?

Answer 8

There is a similarity among species that is inherited from the most recent common ancestor of the group

Question 9

What does it mean if a trait is derived?

Answer 9

There is the similarity that arose more recently (not from a common ancestor)

Question 10

What is cladistics?

Answer 10

A taxonomic technique used for creating hierarchy or organisms that represent true phylogenetic relationships and descent

Question 11

What type of traits are characters considered informative?

Answer 11

derived

Question 12

What are the different types of data that systematics can gather on a number of characteristics?

Answer 12

1. phenotype
2. morphology
3. physiology
4. behavior
5. DNA

Question 13

What does it mean to polarize?

Answer 13

To determine whether a character state are ancestral or derived

Question 14

What is a character state?

Answer 14

one of two or more distinguishable forms of a character ( ex. presence or absence of vertebrate

Question 15

What is used to assign character polarity?

Answer 15

an outgroup

Question 16

What is an outgroup?

Answer 16

a species or group of species that is closely related, but not a member of the group under study

Question 17

What is a clade?

Answer 17

species that share a common ancestor

Question 18

What is synapomorphy?

Answer 18

a derived character shared by clade member

Question 19

What are plesiomorphies?

Answer 19

ancestral states

Question 20

What is symplesiomorphy?

Answer 20

shared ancestral states

Question 21

What are some complications with constructing a cladogram?

Answer 21

the same character could have evolved independently in several species
2. re-evolve evolution

Question 22

What is Homoplasy?

Answer 22

a shared derived character state that has not been inherited from a common ancestor

Question 23

What is the principle of parsimony?

Answer 23

scientists should favor the hypothesis that required the fewest assumptions

Question 24

What is the statistical approach?

Answer 24

an assumption about the rate at which characters evolve and then fit the data to these models to derive the phylogeny that best accords with these assumptions.

Question 25

What is the molecular clock?

Answer 25

the metric in which the rate of evolution

Question 26

what is classification?

Answer 26

how we place species and higher groups-genus, family, class, and so forth- into the taxonomic hierarchy

Question 27

What is taxonomy?

Answer 27

the science of classifying living things

Question 28

What is the first word used to classify a species?

Answer 28

The genus to which the organism belongs to

Question 29

What is the second word in classifying a species?

Answer 29

particular species

Question 30

____ with common properties are in the same class

Answer 30

order

Question 31

_____ have similar characteristics and same phylum

Answer 31

classes

Question 32

____ are assigned to kingdoms

Answer 32

phyla

Question 33

What includes the most recent common ancestor of the group and all of its descendants?

Answer 33

monophyletic

Question 34

What is the term for when it includes the most recent common ancestors of the group but not all its descendants?

Answer 34

paraphyletic

Question 35

What is group does not include the most recent common ancestors of all members in the group?

Answer 35

polyphyletic

Question 36

What is the phylogenetic species concept?

Answer 36

it proposes that the term species should be applied to a group of populations that have been evolving independently of other groups of populations

Question 37

What are some controversies with the phylogenetic species concept?

Answer 37

1. it can lead to the recognition of every slightly differentiated species population as a distinct species 2. species may not always be monophyletic

Question 38

What is a homologous structure?

Answer 38

they are derived from the same body part of a common ancestor

Question 39

what is a homoplastic structure?

Answer 39

they are not derived from a common ancestor