CHAPTER 19

Question 1

systematics

Answer 1

the study of biodiversity, which helps us understand the evolutionary relationships between species. systemics is a quantitative science that uses traits of living and fossil organisms to infer the relationships among organisms over time

Question 2

taxonomy

Answer 2

the branch of systematic biology that identifies, names, and organizes biodiversity into related categories

Question 3

taxon

Answer 3

the general name for a group containing an organism or a group of organisms that exhibits a set of shared traitscla

Question 4

classification

Answer 4

the process of naming and assigning organisms or groups of organisms to a taxon

Question 5

taxonomists

Answer 5

scientists who study taxonomy, strive to classify all of the life on earth. the methods used to classify living organisms have changed throughout history

Question 6

natural groups

Answer 6

groupings of organisms that represent a shared evolutionary history

Question 7

phylogeny

Answer 7

or evolutionary “family tree,” that represents the evolutionary history of taxa. the evolutionary history is then used to classify taxa based on shared ancestry

Question 8

binomial nomenclature

Answer 8

part of his classification system in which each species receives a unique two-part latin name

Question 9

specific epithet

Answer 9

refers to one species within that genus. the second word of the scientific name

Question 10

nomenclature

Answer 10

the procedure of assigning scientific names to taxonoic groups

Question 11

five-kingdom system

Answer 11

monera, protista, fungi, plantae, and animalia

Question 12

common ancestor

Answer 12

an ancestor to two or more lines of descentl

Question 13

lineage

Answer 13

in a phylogeny represents a descendant of a common ancestor

Question 14

diverge

Answer 14

when a new character evolves, a new evolutionary path can begin, or diverge, from the old, a new lineage is formed, and a new branch of the phylogeny arises

Question 15

ancestral traits

Answer 15

those found in the common ancestor, are not useful for determining the evolutionary relationships of an ancestor’s descendants

Question 16

derived traits

Answer 16

those not found in the common ancestor of a taxonomic group, are the most important traits for clarifying evolutionary relationships

Question 17

cladistics

Answer 17

a method that uses shared, derived traits, to develop a hypothesis of evolutionary history

Question 18

cladogram

Answer 18

the evolutionary history of derived traits is interpreted into a type of phylogeny constructed with cladistic methods, called a cladogram

Question 19

clade

Answer 19

in a cladogram, a common ancestor and all of its descendant lineages is called a clade

Question 20

parsimony

Answer 20

cladistics applies the principle of parsimony to a set of traits to construct a cladogram. parsimony considers the simplest solution to be the most “optimal” solution

Question 21

outgroup & ingroup

Answer 21

the taxon that is used to determine the ancestral and derived states of characters in the ingroup, or the taxa for which the evolutionary relationships are being determined

Question 22

homology

Answer 22

a structural similarity that stems from having a common ancestor

Question 23

homologous structures

Answer 23

are similar to each other because of common descent

Question 24

convergent evolution

Answer 24

has occurred when distantly related species have a structure that looks the same only because of adaptation to the same type of environment

Question 25

analogy

Answer 25

similarity due to convergence is termed analogy. the wings of an insect and the wings of a bat are analogous

Question 26

analogous structures

Answer 26

have the same function in different groups but do not have a common ancestry

Question 27

molecular clock

Answer 27

these neutral mutations can be used as a kind of molecular clock to construct a timeline of evolutionary history