26

Question 1

shared ancestral character

Answer 1

character that originated in an ancestor of the taxon

Question 2

shared derived character

Answer 2

an evolutionary novelty unique to a particular clade

hair is an example of this in mammals

Question 3

Phylogenies are inferred from _____ and _______

Answer 3

morphological and molecular data

Question 4

clade

Answer 4

a monophyletic group that includes an ancestral species and all of its descendant s

a group of taxa that includes an ancestor and all its descendants

Question 5

systematics

Answer 5

establishing degrees of relatedness (evolutionary relationships) among both living and extinct species.

Question 6

phylogeny

Answer 6

the evolutionary history of a taxonomic group

evolutionary history of species or groups of species

Question 7

Phylogenetic tree

Answer 7

a graphical summary of this history

Question 8

homologies

Answer 8

Phenotypic and genetic similarities due to shared ancestry

Question 9

analogy

Answer 9

similarity due to convergent evolution

Question 10

Cladistics

Answer 10

an approach to systematics where common ancestry is the primary criterion used to classify organisms

Question 11

taxonomy

Answer 11

how organisms are named and classified

Question 12

sister taxa

Answer 12

groups of organisms that share an immediate common ancestor that is not shared by any other group (chimps and humans)
• Sister taxa usually refer to the tips

Question 13

Monophyletic

Answer 13

“single tribe”- signifying that it consists of an ancestral species and all of its descendants

Question 14

Paraphyletic

Answer 14

“beside the tribe”- consists of an ancestral species and some but not all of its descendants

Question 15

Polyphyletic

Answer 15

“many tribes”- includes distantly related species but DOES NOT include their most recent common ancestor

Question 16

plesiomorph

Answer 16

An organism which represents a primitive state of evolution relative to another organism.

Question 17

apomorph

Answer 17

An organism existing in an evolutionary state that represents a morphological change as compared to a previous state.

Question 18

synapomorphs

Answer 18

a characteristic present in an ancestral species and shared exclusively (in more or less modified form) by its evolutionary descendants.
possession by two or more organisms of a characteristic inherited exclusively from their common ancestor.

Question 19

maximum parsimony

Answer 19

simplest explanation that is consistent with the facts

used to determine the best possible evolutionary relationship among the ingroup taxa, measured by the fewest required character changes.

Question 20

The scientific discipline concerned with naming an organism is called

Answer 20

taxonomy

Question 21

The best classification system is that which most closely

Answer 21

reflects evolutionary history

Question 22

According to Darwin, the more closely related two different organisms are, the

Answer 22

the more recently they shared a common ancestor

Question 23

Parasitic species (organisms that feed off of other organisms without killing them) tend to have simple morphologies. Which of the following statements best explains this observation?

Answer 23

Simple morphologies have been naturally selected for in most parasites

Question 24

In a comparison of birds and mammals, having four limbs is

Answer 24

a shared ancestral character.

Question 25

To apply parsimony to constructing a phylogenetic tree,

Answer 25

choose the tree that represents the fewest evolutionary changes, in either DNA sequences or morphology.

Question 26

Three living species X, Y, and Z share a common ancestor T, as do extinct species U and V. A grouping that consists of species T, X, Y, and Z (but not U or V) makes up

Answer 26

a paraphyletic group

Question 27

If you were using cladistics to build a phylogenetic tree of cats, which of the following would be the best outgroup?

Answer 27

wolf

Question 28

what do branch lengths represent?

Answer 28

genetic change. varying branch lengths indicate that the gene has evolved at different rates in different lineages

Question 29

The relative lengths of the frog and mouse branches in the phylogeny in Figure 26.13 indicate that (pg 560)

Answer 29

the homolog has evolved more slowly in mice.

Question 30

phylogenetic trees show _____, not similarities

Answer 30

historical relationships

Question 31

what do branches represent?

Answer 31

populations through time

Question 32

what does a node represent?

Answer 32

where lineages diverge

Question 33

basal taxon

Answer 33

a lineage that diverges from all other members early in history

Question 34

a taxon is equivalent to a clade only if it is _____

Answer 34

monophyletic

Question 35

maximum likelihood

Answer 35

given certain rules about how DNA changes over time, a tree can be found that reflects the most likely sequence of evolutionary events

Question 36

outgroup

Answer 36

a species that is closely related but not part of the group of species we are studying