Chapter 15

Question 1

speciation

Answer 1

the origin of new species

Question 2

macroevolution

Answer 2

major evolutionary changes as speciation

Question 3

reproductive isolation

Answer 3

the inability of different species to interbreed

Question 4

geographic isolation

Answer 4

occurs when a population becomes separated from the rest of the species due to geographic change or movement to an isolated place

Question 5

adaptive radiation

Answer 5

when populations of a species evolve adaptations to a variety of different environments and form diverse new species

Question 6

punctuated equilibrium

Answer 6

long periods of little chnsge are broken by shorter times of more rapid change

Question 7

embryology

Answer 7

the study of how organisms develop from fertilized eggs to fully formed organisms

Question 8

radiometric dating

Answer 8

a method to determine absolute age based on the amount of radioactive isotopes a fossil contains

Question 9

half-life

Answer 9

scientists use an isotopes half-life to calculate absolute age
(the time it takes for 50% of the original sample to decay)

Question 10

geologic time scale

Answer 10

organized Earth’s history into the Precambrian, Paleozoic, Mesozoic, and Cenozoic eras

Question 11

continental drift

Answer 11

the movement of earths continents on large plates of crust

Question 12

mass extinction

Answer 12

a great species loss called my the “supercontinent” Pangea and that caused major environmental changes and competition between species that had been isolated

Question 13

taxonomy

Answer 13

a branch of biology that involves the identification, naming, and classification of species

Question 14

binomial

Answer 14

two part name (for each species)

Question 15

phylogenetic tree

Answer 15

a diagram that shoes hypothesized evolutionary relationships

Question 16

convergent evolution

Answer 16

a process in which unrelated species from similar environments have adaptations that seem very similar

Question 17

analogous structures

Answer 17

what similar adaptations are called

Question 18

derived characters

Answer 18

homologous structures that do not occur outside a particular evolutionary branch (a clade) in a phylogenetic tree

Question 19

cladogram

Answer 19

are phylogenetic trees that specify the derived characters of clades, to show relationships among organisms

Question 20

biological species concept

Answer 20

defines a species as a population or group of populations whose members have the ability to breed with one another in nature and produce fertile offspring