Evolution of Species

Question 1

adaptation

Answer 1

heritable trait or behavior in an organism that aids in its survival and reproduction in its present environment

Question 2

adaptive radiation

Answer 2

speciation when one species radiates to form several other species

Question 3

allopatric speciation

Answer 3

speciation that occurs via geographic separation

Question 4

allopolyploidy

Answer 4

polyploidy formed between two related, but separate species

Question 5

autopolyploidy

Answer 5

polyploidy formed within a single species

Question 6

behavioral isolation

Answer 6

type of reproductive isolation that occurs when a specific behavior or lack of one prevents reproduction from taking place

Question 7

biological species concept

Answer 7

a group of organisms that can successfully interbreed and produce fertile offspring

Question 8

dispersal

Answer 8

allopatric speciation that occurs when a few members of a species move to a new geographical area

Question 9

ecological species concept

Answer 9

a concept of species in which a species is a set of organisms adapted to a particular set of resources, called a niche, in the environment

Question 10

evolutionary species concept

Answer 10

a single lineage of ancestor-descendant populations of organisms which maintains its identity from other such lineages

Question 11

gametic barrier

Answer 11

prezygotic barrier occurring when closely related individuals of different species mate, but differences in their gamete cells prevent fertilization from taking place

Question 12

gradual speciation model

Answer 12

model that shows how species diverge gradually over time in small steps

Question 13

habitat (ecological) isolation

Answer 13

reproductive isolation resulting when species’ populations move or are moved to a new habitat, taking up residence in a place that no longer overlaps with the same species’ other populations

Question 14

hybrid

Answer 14

offspring of two closely related individuals, not of the same species

Question 15

hybrid inviability

Answer 15

a situation in which a mating between two individuals creates a hybrid that does not survive past the embryonic stages

Question 16

hybrid zone

Answer 16

area where two closely related species continue to interact and reproduce, forming hybrids

Question 17

mechanical isolation

Answer 17

a physical incompatibility between reproductive organs of two organisms

Question 18

morphospecies concept

Answer 18

species designated and clearly separated from other species based on recognized unequivocal morphological features

Question 19

postzygotic barrier

Answer 19

reproductive isolation mechanism that occurs after zygotic formation

Question 20

prezygotic barrier

Answer 20

reproductive isolation mechanism that occurs before zygote formation

Question 21

punctuated equilibrium

Answer 21

model for rapid speciation that can occur when an event causes a small portion of a population to be cut off from the rest of the population

Question 22

reinforcement

Answer 22

continued speciation divergence between two related species due to low fitness of hybrids between them

Question 23

speciation

Answer 23

formation of a new species

Question 24

species

Answer 24

group of populations that interbreed and produce fertile offspring

Question 25

sympatric speciation

Answer 25

speciation that occurs in the same geographic space

Question 26

temporal isolation

Answer 26

differences in breeding schedules that can act as a form of prezygotic barrier leading to reproductive isolation

Question 27

vicariance

Answer 27

allopatric speciation that occurs when something in the environment separates organisms of the same species into separate groups