Practice Questions

Exam 1

Questions about Introduction to Darwinism


"Differential success in reproduction" is just another way of saying _____.

natural selection
genetic drift


The smallest unit that can evolve is a _____.



Which of the following is a true statement about Charles Darwin?

He was the first to discover that living things can change, or evolve.
He based his theory on the inheritance of acquired characteristics.
He worked out the principles of population genetics.
He proposed natural selection as the mechanism of evolution.
He was the first to realize that Earth is billions of years old.


"Natural selection" and "evolution" are two terms that are sometimes confused, even by freshman biology students. What is the relation between natural selection and evolution?

They are the same thing.
Any phenomenon that causes evolution is natural selection.
Natural selection is one of several causes of evolution.
When natural selection is occurring, evolution is not, and vice versa.
None of the above.


The science of classifying organisms is called _____.



The scala naturae, or hierarchy of nature, is based on the ideas of _____.



At the time Darwin voyaged on HMS Beagle, the popularly accepted theory in Europe that explained the origin of Earth's plants and animals held that the various species ____________.

arose continually from nonliving materials by spontaneous generation
had been created by divine intervention a few thousand years before
had evolved from now extinct organisms
arose from a single species that had survived the biblical flood
were all related to one another


At the time Charles Darwin sailed on HMS Beagle ___________.

the idea that animals and plants might change over time was absent from Western science, but was accepted in Arabic science
several biologists had proposed that species might change over time, but none had suggested a convincing mechanism that might cause the change
the idea of evolution was widely accepted because it was a part of the biblical story of creation
the idea of evolution was widely accepted by scientists, but Darwin's great impact was to popularize it for the layperson
none of the above


During his voyage around the world, Darwin was inspired to think about evolution by _____.

the books he read
fossils he collected
the studying adaptations of organisms to their environments
the unique organisms he saw in the Galápagos Islands
all of the above


The breeding of plants and animals by humans is called _____.

natural selection
sexual recombination
founder effect
artificial selection
neutral variation

German shorthaired pointers, Scottish terriers, and beagles are capable of interbreeding and producing viable, fertile offspring. The diversity in morphologies seen in these breeds of dogs is the result of _____.

natural selection
sexual recombination during meiosis
artificial selection
Any of the above could have produced these and the other currently recognized breeds of dogs


Which of the following factors is NOT an important part of natural selection?

limited environmental resources
unequal reproduction with individuals best meeting environmental demands having the most success
heritable variation
selective breeding of domestic plants and animals
individuals better adapted to an environment being more likely to survive


Assume there are two varieties of mice, brown and gray, living on an island. They are the prey for the hawks on the island. They are distributed through rocky areas in the north of the island and across the fields in the south part. Which of the following is predicted by natural selection?

If they stay as a mixed population, they will remain mixed because the two varieties will not interbreed with each other.
Since brown mice blend better with the ground and gray mice blend better with the rocks, these are the ones that will be missed by the hawks and the mouse distribution will tend to indicate this.
Hawks find the mice by movement so it won't matter.
The hawks will starve to death because they get confused.
A mouse population that starts as a random mixture will never adapt to the environment.


Natural selection primarily favors _____.



The main ideas of Darwin's theory of evolution came from his observations of life on the Galápagos Islands. Where are these islands located?

off the west coast of South America
off the east coast of South America
in the Indian Ocean
southeast of Australia
southwest of Australia


If members of a population have phenotypic traits that are both heritable and variable among individuals, then ___________.

advantageous traits may become more widespread in subsequent generations
no evolutionary change is likely to occur over time
only neutral evolutionary change can occur over time
the environment will have no influence on phenotypes
genotypes will have no influence on phenotypes


When they were first sold, aerosol insecticides were highly effective in killing flies and mosquitoes. Today, some 30 years later, a much smaller proportion of these insects die when sprayed. The reason fewer insects are being killed is that ____________.

mosquitoes that survive spraying develop an immunity to the insecticide
many mosquitoes today are descendants of mosquitoes with insecticide-resistant characteristics
mosquitoes are deliberately adapting themselves to this man-made change in the environment
the original spraying has caused a permanent mutation, giving the insects genetic resistance to the spray
none of the above


An important challenge to traditional (pre-1860) ideas about species was the observation that seemingly dissimilar organisms, such as hummingbirds, humans, and whales, have similar skeletal structures. This most directly suggested to biologists that ____________.

only the best-adapted organisms can survive
advantageous changes can be passed along to offspring
most evolution occurs rapidly following a mass extinction
dissimilar organisms might have evolved from a distant, common ancestor
all of the above


Darwin inferred that individuals of a species compete with one another, observing that _____.

some individuals are larger and stronger than others
natural population sizes do not usually expand exponentially
many different phenotypes coexist within a species
some peas have purple flowers while others have white flowers
gene frequencies in a population change over time


Traits that enhance an individual's ability to compete for limited resources are called _____.

isolating mechanisms


Which one of the following statements most closely agrees with the theory of evolution by means of natural selection, as put forth by Darwin and Wallace?

Only the best-adapted organisms will survive.
Humans arose from chimpanzees.
Organisms mutate under unfavorable conditions to become better adapted.
Only favorable traits are passed from one generation to the next.
Organisms better adapted to their immediate environment are most likely to survive and reproduce.


Which one of the following statements best reflects Darwin's view of human evolution?

Humans are descended from monkeys.
Humans are the product of artificial selection.
Humans and apes have a common ancestor.
Humans are not a product of evolution.
Humans are more abundant than any other animal species.


In natural selection, __________ determines which phenotypes are successful.

the environment
sample size
genetic drift
human intervention


Which one of the following is NOT a requirement for, nor a feature of, natural selection?

excess numbers of individuals
variation in individuals
heritable traits
greater numbers of offspring from the better adapted
environmentally induced acquisition of traits


The major weakness of Darwin's theory (as it existed in 1859) was that it could NOT explain _____.

why species become extinct
why different parts of the world have different plants and animals
why vestigial structures exist
how advantageous traits can be passed to offspring
any of the above


Which of the following was NOT a part of Darwin's explanation of natural selection?

Most organisms commonly produce more offspring than can possibly survive.
Mutation (a change in DNA structure) occurs spontaneously and gives rise to new variations.
Species consist of individuals that vary from one another.
Members of a species compete with each other for food and space.
Some traits confer a reproductive advantage and are passed along more frequently than others.


Animals that possess homologous structures probably _____.

are headed for extinction
evolved from the same ancestor
have increased genetic diversity
by chance had similar mutations in the past
are not related


The approach to evolution that involves the study of similar structures that appear during the development of different organisms is known as the study of _____.

comparative anatomy
embryological homologies (comparative embryology)
molecular biology

All known organisms transcribe genetic information to protein molecules via the same genetic code. This finding strongly supports the hypothesis that _____.

there's only one possible way to encode information in a macromolecule
the earliest macromolecules probably arose when lightning struck an oxygen-free atmosphere
all organisms are descended from a single common ancestor
the genetic code will never be broken
none of the above


Darwin was well aware of what effect his theory of evolution would have on the lay public and on the Church of England. This, in fact, was why he delayed publication for several decades while he gathered additional evidence. Which one of the following was NOT evidence he used to support his theory?

Earth is about 6,000 years old.
Many more offspring are produced than can survive.
When breeders select for specific traits, these become fixed in future generations.
Some individuals leave more descendants than other individuals.
In a population of organisms, every individual is different from every other one.


Evidence from molecular biology supports the theory of evolution by showing that _____.

homologous proteins have arisen separately in many different animal groups
closely related animal species have similar geographic distributions
closely related organisms have more similar DNA and proteins
closely related organisms have similar stages of development
none of the above

Answers: 1. A; 2. D; 3. D; 4. C; 5. D; 6. C; 7. B; 8. B; 9. E; 10. D; 11. C; 12. D; 13. B; 14. A; 15. A; 16. A; 17. B; 18. D; 19. B; 20. B; 21. E; 22.C; 23. B; 24. E; 25. D; 26. B; 27. B; 28. B; 29. C; 30. A; 31. C