Chapter 25 Phylogeny and Systematics

Question 1

what is Systematics?

Answer 1

Systematics is the study of biological diversity in an evolutionary context.

Question 2

what does a systematist seeks to do?

Answer 2

A systematistseeks to learn an organism’s phylogeny.

Question 3

what is a Phylogeny?

Answer 3

Phylogeny is the evolutionary history of a species or group of related species.

Question 4

what 3 kinds of data can be used to study phylogeny?

Answer 4

Biologists use evidence from paleontology,
molecular data, comparative anatomy, and
other approaches to study phylogeny.

Question 5

what is taxonomy

Answer 5

Systematics includes taxonomy, the naming and classification of species and groups of species

Question 6

what is a The specific epithet?

Answer 6

The specific epithetrefers to one species

within each genus.

Question 7

taxonomy makes use of what system?

Answer 7

Taxonomy makes use of the Linnean

System

Question 8

true or false: The more homologous parts that two species share, the more closely related they are.

Answer 8

true The more homologous parts that two species share, the more closely related they are.

Question 9

another term for heritable traits

Answer 9

Character = heritable traits

Question 10

what are character states?

Answer 10

variants of the trait

Question 11

what are Symplesiomorphies ?

Answer 11

Symplesiomorphies = shared, ancestral traits

Question 12

true or false :Shared primitive characters are useful in determining phylogeny.

Answer 12

false • Shared primitive characters are not useful in determining phylogeny.

Question 13

what is outgroup comparison for?

Answer 13

outgroup comparison which is used to

differentiate shared primitive characters from shared derived ones

Question 14

what is an outgroup?

Answer 14

An outgroup is a species or group of species that is closely related to the species that we are studying, but known to be less closely related than any study-group members are to each other.

Question 15

what is an outgroup analysis?

Answer 15

In an outgroup analysis, the assumption is that any homologies shared by the ingroup and outgroup must be primitive characters already present in the ancestor common to both groups.

Question 16

define ingroup

Answer 16

Ingroup = taxa in the group under study

Question 17

define outgroup

Answer 17

Outgroup = taxa that are closely related to the ingroup

Question 18

define The principle of parsimony

Answer 18

• a theory about nature should be the simplest
explanation consistent with the facts.
• In phylogenetic analysis, parsimony is used to justify the choice of a tree that represents the smallest number of evolutionary changes.

Question 19

true or false:For many species’ characters, hereditary fidelity (staying the same) is less common than change.

Answer 19

false: For many species’ characters, hereditary fidelity (staying the same) is more common than change.

Question 20

true or false The least reliable trees are based on the largest data base.

Answer 20

false The most reliable trees are based on the largest data base.