Question 1

A study by Charles and Mary Brown has documented a reduction in the wing length of cliff swallows that live near busy roadways; the study proposes that the need to avoid being hit by cars is the evolutionary driving force for the change.How would you evaluate this hypothesis if wing length had also shortened in cliff swallow populations that live in the desert Southwest where traffic is virtually nonexistent?

Accepted Answer

A)  The hypothesis would still be valid. Natural selection is driven by local conditions; the two populations are probably evolving independently and they have coincidentally acquired the same characteristics. 
B)  The hypothesis would raise some doubts; perhaps aerial predators or another factor yet to be identified are creating the necessity for better flying skills in both populations. 
C)  The hypothesis would not be valid, because the probability of the same wing length mutation arising in geographically distinct populations is extremely low. 
D)  The hypothesis would not be valid; if the need to avoid vehicular collisions is driving natural selection, then no evolution should be occurring in the population that lives in the traffic-free environment.

Question 2

Humans have a reduced tailbone and the muscles to move a tail.This evidence indicates that we descended from an ancestor that had a tail.

Accepted Answer

A) True 
 B)False

Question 3

In genetic drift,the events that affect the survival and reproduction of individuals in a population occur

Accepted Answer

A)  primarily by chance. 
B)  in a predictable way. 
C)  rapidly and in close succession. 
D)  in close association with geological processes.

Question 4

The fossils of organisms that existed when the continents were connected are distributed across ________ continents than the fossils of organisms that evolved after the continents separated.

Accepted Answer

The answer of The fossils of organisms that existed when...

Question 5

Evolution is

Accepted Answer

A)  not supported by scientific evidence. 
B)  strongly supported by scientific evidence. 
C)  not supported by the fossil record. 
D)  too obscure to study.

Question 6

Natural selection tends to

Accepted Answer

A)  increase the commonality of characteristics that enhance survival and reproduction. 
B)  decrease the number of individuals in any given population. 
C)  lead to an increase in genetic drift. 
D)  decrease the likelihood of adaptation.

Question 7

Genetic variation is based on

Accepted Answer

A)  the inheritance of alleles that are accumulated during an individual's lifetime. 
B)  differences in DNA sequences between the individuals in a population. 
C)  the accumulation of mutations in somatic cells (as opposed to gametes). 
D)  the formation of new combinations of alleles during asexual reproduction.

Question 8

As embryos,baleen whales have teeth and also have two nostrils directly above their mouth.Before birth,however,the teeth are reabsorbed,and the nostrils migrate and fuse to become the blowhole.What does this observation suggest about the ancestry of these whales?

Accepted Answer

A)  Baleen whales descended from an aquatic ancestor that breathed through an elongated snout, much like the modern alligator does today. 
B)  Baleen whale ancestors lived in habitats where the potential for mutation was relatively high; early abnormalities during embryonic development are later corrected before birth. 
C)  Baleen whales evolved from a terrestrial mammalian ancestor and share common inherited developmental features. 
D)  Modern terrestrial mammals are descended from the same marine mammal ancestors that gave rise to modern whales.

Question 9

In ________ selection,success is related more to attracting a mate than to possessing adaptations that are beneficial for survival.

Accepted Answer

The answer of In ________ selection,success is related more to...

Question 10

Darwin's ideas about natural selection were immediately accepted; this shows that the scientific community recognizes and accepts correct ideas as soon as they are presented.

Accepted Answer

A) True 
 B)False

Question 11

Humans have bred cows that are specialized for milk production by mating female cows that produce large quantities of milk with male cows whose mothers also produced large quantities of milk.This is an example of ________ selection.

Accepted Answer

The answer of Humans have bred cows that are specialized...

Question 12

Peppered moths are generally light in color and blend into the trunks of the trees they live on.Populations of peppered moths that are found in areas where soot has blackened the tree trunks are dark in color.This example demonstrates

Accepted Answer

A)  artificial selection. 
B)  natural selection. 
C)  genetic drift. 
D)  vestigial coloration.

Question 13

Plate tectonics causes the ________ of Earth's landmasses over geologic time.

Accepted Answer

The answer of Plate tectonics causes the ________ of Earth's...

Question 14

Which of the following statements about the evolutionary relatedness of organisms is FALSE?

Accepted Answer

A)  Predictions of evolutionary relatedness that are based on the fossil record often agree with predictions that are based on continental drift. 
B)  Predictions of evolutionary relatedness that are based on fossil evidence often agree with those that are based on protein sequences. 
C)  Predictions of evolutionary relatedness that are based on DNA often contradict those that are based on anatomical evidence. 
D)  Predictions that are based on DNA sequences provide the strongest evidence that two organisms are related.

Question 15

Many organisms are darker on their dorsal surface and lighter on their ventral surface.They are difficult to see from both above and below because of this ________,which is called countershading.

Accepted Answer

A)  adaptation 
B)  pattern of resistance 
C)  selection pressure 
D)  fixation

Question 16

Which of the following things is an example of gene flow?

Accepted Answer

A)  an insecticide, like DDT, that improves reproductive success for only those individuals that have the genes for resistance 
B)  the selective removal of visually distinctive individuals via predation 
C)  the post-bottleneck expansion of a population after the restriction has been removed 
D)  pollen grains that can transport a gamete hundreds of miles to an isolated population

Question 17

Cliff swallows in southwestern Nebraska are experiencing a new natural selection pressure; the swallows that are less agile are more likely to be killed by ________.

Accepted Answer

The answer of Cliff swallows in southwestern Nebraska are experiencing...

Question 18

One frequently observed example of evolution is

Accepted Answer

A)  a chameleon changing colors as it moves from a leaf of one color to a leaf of another color. 
B)  bacteria developing increased resistance to an antibiotic that is used to kill them. 
C)  chimpanzees learning sign language. 
D)  humans teaching dogs to obey certain commands.

Question 19

The genus Lycopodium includes plants that evolved before the breakup of Pangaea.The genus Sequoiadendron (redwood trees)evolved after Pangaea split into separate landmasses.Which genus would you expect to have the widest distribution of living representatives across the modern continents?

Accepted Answer

A)  Lycopodium 
B)  Sequoiadendron 
C)  Both should be equally distributed. 
D)  Both should be extinct.

Question 20

Pangaea is

Accepted Answer

A)  the component of plate tectonics that was formerly called continental drift. 
B)  the combined fossil record of ancient species. 
C)  an ancient supercontinent formed from the major landmasses that exist today as separate continents. 
D)  the result of natural selection.

Exam 14: How Evolution Works