14. Speciation and Extinction

Question 1

large-scale evolutionary change

Answer 1

Macroevolution

Question 2

a distinct type of organism

Answer 2

Species

Question 3

a population, or group of populations, whose members can interbreed and produce fertile offspring

Answer 3

Biological Species

Question 4

formation of new species

Answer 4

Speciation

Question 5

all of the genes and their alleles in a population

Answer 5

Gene Pool

Question 6

producing a mix of offspring for one or more traits; heterozygous

Answer 6

Hybrid(Genetics)

Question 7

separation of species due to factors that prevent the formation of a zygote;

Answer 7

prezygotic reproductive isolation

Question 8

separation of species due to selection against hybrid offspring

Answer 8

postzygotic reproductive isolation

Question 9

formation of new species after a physical barrier separates a population into groups that cannot interbreed

Answer 9

allopatric speciation

Question 10

formation of new species when part of a population enters a habitat bordering the parent species’ range, and the two groups become reproductively isolated

Answer 10

parapatric speciation

Question 11

cell with extra chromosome sets

Answer 11

polyploid cell

Question 11

theory that proposes that evolutionary change occurs gradually, in a series of small steps

Answer 11

gradualism

Question 11

formation of a new species within the habitat boundaries of a parent species

Answer 11

sympatric speciation

Question 11

theory that life’s history has been characterized by bursts of rapid evolution interrupting long periods of little change

Answer 11

punctuated equilibrium

Question 12

divergence of multiple new species from a single ancestral type in a relatively short time

Answer 12

adaptive radiation

Question 13

steady, gradual loss of species through natural competition or loss of genetic diversity

Answer 13

background extinction rate

Question 14

the disappearance of many species over relatively short expanses of time

Answer 14

mass extinction

Question 15

idea that mass extinctions were caused by impacts of extraterrestrial origin

Answer 15

impact theory

Question 16

field of study that includes taxonomy and phylogenetics

Answer 16

systematics

Question 17

the science of describing, naming, and classifying organisms

Answer 17

taxonomy

Question 18

field of study that attempts to explain the evolutionary relationships among species

Answer 18

phylogenetics

Question 19

phylogenetic system that defines groups by distinguishing between ancestral and derived characters

Answer 19

cladistics

Question 20

characteristic already present in the ancestor of a group being studied

Answer 20

ancestral character

Question 21

characteristic not found in the ancestor of a group being studied

Answer 21

derived character

Question 22

basis for comparison in a cladistics analysis

Answer 22

outgroup

Question 23

treelike diagram built using shared derived characteristics

Answer 23

cladogram

Question 24

monophyletic group of organisms consisting of a common ancestor and all of its descendants

Answer 24

clade

Question 25

describes a group of organisms consisting of a common ancestor and all of its descendants (a clade)

Answer 25

monophyletic

Question 26

in cladistics, describes the evolutionary tree that requires the fewest steps to construct from a set of observations

Answer 26

parsimonious

Question 27

describes a group of organisms that contains a common ancestor and some, but not all, of its descendants

Answer 27

paraphyletic

Question 28

describes a group of organisms that excludes the most recent common ancestor of all members of the group

Answer 28

polyphyletic