Chapter 15: Tracing Evolutionary History

Question 1

define adaptive radiations

Answer 1

periods of evolutionary change in which many new species evolve from a common ancestor

Question 2

when do adaptive radiations often occur?

Answer 2

following the colonization of new unexploited areas or evolutionary innovations

Question 3

what can result in adaptive radiations?

Answer 3

colonization

Question 4

evolution acts upon

Answer 4

available diversity

Question 5

“Evo-devo” combines…

Answer 5

evolutionary and developmental biology

Question 6

new forms can evolve by…

Answer 6

changes in the number, sequences, or regulation of developmental genes

Question 7

homeotic genes are AKA

Answer 7

master control genes

Question 8

homeotic genes determine…

Answer 8

basic features

-where pairs of wings/legs develop on a fruit fly

Question 9

profound alterations in body form can result from..

Answer 9

• changes in homeotic genes

- how/where homeotic genes are expressed

Question 10

what might have facilitated the origin of new body forms?

Answer 10

new developmental genes that arose as a result of gene duplications

Question 11

timing of gene expression changes…

Answer 11

phenotype

Question 12

define heterochrony…

Answer 12

genetically controlled difference in timing/duration of a developmental process in an organism

Question 13

describe the evolution of novel traits…

Answer 13

complex structures that evolve in stages from simpler version with

• the same basic function
• gradual adaptation of existing structures to new functions

Question 14

define exaptation

Answer 14

co-opting a trait that evolved in one circumstance for a novel function

Question 15

feathers are…

Answer 15

specialized forms of scales

Question 16

an evolutionary trend may be the result of…

Answer 16

species persistence of natural selection in changing environments

Question 17

define taxonomy

Answer 17

branch in biology concerned with identifying, naming, and classifying species

Question 18

define a binomial

Answer 18

two-part scientific name assigned to species

Question 19

describe the parts to a binomial name…

Answer 19

• genus

- specific epithet

Question 20

binomials show

Answer 20

shared common ancestry

Question 21

specific epithets

Answer 21

can be shared

Question 22

define a phylogeny

Answer 22

the evolutionary history of a species or group of species

Question 23

define systematics

Answer 23

discipline of biology that focuses on classifying organisms and determining their evolutionary relationships

Question 24

define phylogenetic tree

Answer 24

a hypothesis of evolutionary relationships

Question 25

a phylogenetic tree is constructed from…

Answer 25

homologous characters

Question 26

what provides the evidence of common ancestry that’s used to determine phylogeny?

Answer 26

homologous structures and molecular sequences

Question 27

define convergent evolution

Answer 27

similarities due to the similar adaptations in organisms from different evolutionary lineages

Question 28

define analogy

Answer 28

similarity due to convergent evolution

Question 29

birds and human forearm bones are

Answer 29

not homologous as wing but analogous as wings

Question 30

flippers are ______, why?

Answer 30

analogous

bc they do not share a common ancester

Question 31

cladistics groups

Answer 31

organisms on a phylogeny by common ancestry

Question 32

define a monophyletic group

Answer 32

group consisting of ancestral species and all of its evolutionary descendants

Question 33

paraphyletic and polyphyletic groups are NOT

Answer 33

natural

Question 34

an organism’s evolutionary history is documented in its

Answer 34

genome

Question 35

similar DNA sequences indicate

Answer 35

two species that have recently branched from a common ancestor

Question 36

molecular systematics uses

Answer 36

DNA or other molecules to infer relatedness

Question 37

homologous genes are found across

Answer 37

distantly related species

Question 38

homologous genes can suffer from

Answer 38

convergent evolution or oversaturation

Question 39

a molecular clock is a method that

Answer 39

estimates the time required for a certain amount of evolutionary change

Question 40

what helps classify the major divisions in life?

Answer 40

molecular clock

Question 41

the tree of life is originally based on

Answer 41

rDNA

Question 42

what are the 3 domains that life is currently classified into?

Answer 42

1. eukarya
2. bacteria
3. archaea

Question 43

the tree of life shows us…

Answer 43

multiple horizontal gene transfers

Question 44

these horizontal gene transfers include

Answer 44

transfers that resulted in the origin of eukaryotic cells

Question 45

examples of horizontal gene transfers…

Answer 45

the endosymbiosis of mitochondria and chloroplasts