Biology Ch. 15 Vocabulary

Question 1

Darwin’s term for the selective breeding of organisms selected for certain traits in order to produce offspring having those traits

Answer 1

Artificial selection

Question 2

Theory of evolution developed by Darwin, based on four ideas: excess reproduction, variations, inheritance, and the advantages of specific traits in an environment

Answer 2

Natural selection

Question 3

Hereditary changes in groups of living organisms over time

Answer 3

Evolution

Question 4

New feature that had not appeared in common ancestors

Answer 4

Derived trait

Question 5

More-primitive characteristic that appeared in common ancestors

Answer 5

Ancestral trait

Question 6

Anatomically similar structure inherited from a common ancestor

Answer 6

Homologous structure

Question 7

Reduced form of a functional structure that indicates shared ancestry

Answer 7

Vestigial structure

Question 8

Structure that has the same function but different construction and was not inherited from a common ancestor

Answer 8

Analogous structure

Question 9

Organism’s early pre birth stage of development

Answer 9

Embryo

Question 10

Study of the distribution of plants and animals on Earth

Answer 10

Biogeography

Question 11

Measure of a trait’s relative contribution to the following generation

Answer 11

Fitness

Question 12

Morphological adaptations that allow organisms to blend into their surroundings

Answer 12

Camouflage

Question 13

Morphological adaptation in which one species evolves to resemble another species for protection or other advantages

Answer 13

Mimicry

Question 14

Random change in allelic frequencies in a population

Answer 14

Genetic drift

Question 15

Random effect that can occur when a small population settles in an area separated from the rest of the population and interbreeds, producing unique allelic variations

Answer 15

Founder effect

Question 16

Change in the frequency of a trait based on competition for a mate

Answer 16

Sexual selection

Question 17

Most common form of natural selection in which organisms with extreme expressions of a trait are removed

Answer 17

Stabilizing selection

Question 18

Shift of a population toward an extreme version of a beneficial trait

Answer 18

Directional selection

Question 19

Process in which individuals with average traits are removed, creating two populations with extreme traits

Answer 19

Disruptive selection

Question 20

Factor that prevents individuals from different species from mating: operates before fertilization

Answer 20

Prezygotic isolating mechanism

Question 21

Factor that prevents a hybrid zygote from developing, or prevents hybrid offspring from reproducing, operates after fertilization

Answer 21

Postzygotic isolating mechanism

Question 22

Occurs when a population divided by a geographic barrier evolves into two or more populations unable to interbreed

Answer 22

Allopatric speciation

Question 23

Occurs when a species evolves into a new species in an area without a geographic barrier

Answer 23

Sympatric speciation

Question 24

Diversification of a species into a number of different species, often over a relatively short time span

Answer 24

Adaptive radiation

Question 25

Theory that evolution occurs in small, gradual steps over time

Answer 25

Gradualism

Question 26

Theory that evolution occurs with relatively sudden periods of speciations followed by long periods of stability

Answer 26

Punctuated equilibrium