Chapter 17 - Processes Of Evolution Flashcards
Individuals don’t evolve, ____________ do.
populations
Biologists define evolution as _____________.
a. purposeful change in a lineage
b. heritable change in a line of descent
c. acquiring traits during the individual’s lifetime
b. heritable change in a line of descent
___________ is the original source of new alleles.
a. Mutation
b. Natural selection
c. Genetic drift
d. Gene flow
e. All are original sources of new alleles
a. Mutation
Evolution can only occur in a population when ___________.
a. mating is random
b. there is selection pressure
c. neither is necessary
c. neither is necessary
A fire devastates all trees in a wide swath of forest. Populations of a species of tree-dwelling frog on either side of the burned area diverge to become separate species. This is an example of ___________________.
allopatric speciation
Stabilizing selection tends to ____________ (select all that apply).
a. eliminate extreme forms of a trait
b. favor extreme forms of a trait
c. eliminate intermediate forms of a trait
d. favor intermediate forms of a trait
e. shift allele frequencies in one direction
a. eliminate extreme forms of a trait
d. favor intermediate forms of a trait
Disruptive selection tends to _______ (select all that apply).
a. eliminate extreme forms of a trait
b. favor extreme forms of a trait
c. eliminate intermediate forms of a trait
d. favor intermediate forms of a trait
e. shift allele frequencies in one direction
b. favor extreme forms of a trait
c. eliminate intermediate forms of a trait
Directional selection tends to _________ (select all that apply).
a. eliminate extreme forms of a trait
b. favor an extreme form of a trait
c. eliminate intermediate forms of a trait
d. favor intermediate forms of a trait
e. shift allele frequencies in one direction
b. favor an extreme form of a trait
e. shift allele frequencies in one direction
Sexual selection, such as occurs when males compete for access to fertile females, frequently influences aspects of body form and can lead to ______________.
a. male/female differences
b. male aggression
c. exaggerated traits
d. all of the above
d. all of the above
The persistence of malaria and sickle-cell anemia in a population is a case of __________.
a. bottlenecking
b. balanced polymorphism
c. natural selection
d. artificial selection
e. both b and c
e. both b and c
________ tends to keep populations of a species similar to one another.
a. Genetic drift
b. Gene flow
c. Mutation
d. Natural selection
b. Gene flow
In evolutionary trees, each node represents a(n) ______________.
a. single lineage
b. extinction
c. point of divergence
d. adaptive radiation
c. point of divergence
In cladograms, sister groups are __________.
a. inbred
b. the same age
c. represented by nodes
d. in the same family
b. the same age
Match the evolution concepts.
\_\_\_ gene flow \_\_\_ natural selection \_\_\_ mutation \_\_\_ genetic drift \_\_\_ adaptive radiation \_\_\_ coevolution \_\_\_ phylogeny \_\_\_ cladogram
a. can lead to interdependent species
b. changes in a population’s allele frequencies due to chance alone
c. alleles enter or leave a population
d. evolutionary history
e. occurs in different patterns
f. burst of divergences from one lineage into many
g. source of new alleles
h. diagram of sets within sets
Match the evolution concepts.
(c) gene flow
(e) natural selection
(g) mutation
(b) genetic drift
(f) adaptive radiation
(a) coevolution
(d) phylogeny
(h) cladogram
a. can lead to interdependent species
b. changes in a population’s allele frequencies due to chance alone
c. alleles enter or leave a population
d. evolutionary history
e. occurs in different patterns
f. burst of divergences from one lineage into many
g. source of new alleles
h. diagram of sets within sets
