Name ______________________________
Period _____ Date ___________ Seat ____
1. Who observed variations in the characteristics of plants and animals on the Galapagos
a. James Hutton
c. Charles Lyell
b. Thomas Malthus
d. Charles Darwin
2. In different parts of the world, Darwin found unrelated species that looked alike
a. the species lived in different environments.
b. the species lived in similar environments.
c. the species were closely related.
d. the species once lived in the same place.
3. Which of the following ideas proposed by Lamarck was later found to be incorrect?
a. Acquired characteristics can be inherited.
b. All species are descended from other species.
c. Living things change over time.
d. There is a relationship between an organism and its environment.
4. Which of the following would an animal breeder use to increase the amount of milk
given by his herd of cows?
a. overproduction
c. acquired characteristics
b. genetic isolation
d. artificial selection
5. An inherited characteristic that increases an organism’s ability to survive and reproduce
its environment is called a(n)
a. vestigial structure.
c. homologous structure.
b. adaptation.
d. variation.
6. What do evolutionary trees show?
a. all life depends on trees
b. all life is changing due to natural selection
c. all living species are descended from earlier ancestors
d. all life evolves to the point of perfection
7. Series of related fossils are important evidence of evolution because they show
a. how organisms changed over time.
b. how animals behaved in their environments.
c. how the embryos of organisms develop.
d. molecular homologies.
8. The wing of a bird that cannot fly is an example of a(n)
a. analogous structure.
c. vestigial structure.
b. homologous structure.
d. molecular structure.
9. Lyell’s Principles of Geology influenced Darwin because it explained how
a. organisms change over time.
c. Earth must be very old
b. adaptations occur.
d. why finches inhabit the Galapagos
10. The ability of an individual organism to survive and reproduce in its natural environment
is called
a. natural selection
c. descent with modification
b. evolution
d. fitness
11. Which of the following is an important concept in Darwin’s theory of evolution by
natural selection?
a. descent with modification
b. homologous molecules
c. processes that change the surface of Earth
d. the tendency toward perfection
12. Which of the following provides evidence for evolution?
a. fossil record
b. homologous structures of living organisms
c. geographical distribution of living things
d. all of the above
13. DNA and RNA provide evidence of evolution because
a. all organisms have nearly identical DNA and RNA.
b. no two organisms have exactly the same DNA.
c. each RNA codon specifies just one amino acid.
d. in most organisms, the same codons specify for the same amino acids.
Questions 14 and 15
The birds shown below are two of the species of finches Darwin found on the Galapagos Islands.
14. What process produced the two different types of beaks shown?
a. artificial selection
c. geographical distribution
b. natural selection
d. disuse of the beak
15. The large ground finch obtains food by cracking seeds. Its short, strong beak is an
example of
a. the struggle for existence.
c. the tendency toward perfection.
b. an adaptation.
d. a vestigial organ.
What connection did Darwin make between the Galapagos tortoises and their environments?
Closely related Galapagos tortoises exhibited different traits depending on the
environment of the island where they lived.
Why was Darwin’s trip on the Beagle so important to his development of the theory of natural
The trip exposed Darwin to a much greater diversity of life than did his home in
England. He was able to see patterns of biogeography that could be seen only
during world travel.
According to Malthus, what factors limit human population growth?
According to Malthus, population growth is limited to overcrowding and lack of
food, which in turn lead to war, famine, and disease.
Lamarck made a very significant contribution to science, even though his explanation of evolution
was wrong. Explain how Lamarck helped other scientists.
Lamarck was one of the first naturalists to suggest species were not fixed, and he
tried to explain evolution scientifically using natural processes. He also recognized
there is a link between the organisms environment and its body structures.
Although Lamarck’s explanation of how evolutionary change occurs was wrong,
these other ideas paved the way for later biologists, including Darwin.
Could artificial selection happen without inherited variation? Explain your answer.
Artificial selection could not happen without inherited variation, because breeders
select individuals carrying a desired version of a trait over those with other versions
of that trait.
What is fitness, in evolutionary terms?
Individuals that have high fitness are more likely to survive and have more offspring
than low-fitness individuals. Their inherited characteristics are more likely to be
passed on to future generations. Individuals with high fitness in one environment may
not be very fit in another environment.
Many species of birds build nests in which they lay eggs and care for their young. How does this
Behavior relate to reproductive fitness?
Birds that build better nests have a better chance of hatching all of their eggs. Wellconstructed and well-hidden nests are safer from accidents and from predators. More
young will survive to reproduce from well-made nests.
How does DNA provide evidence for common descent?
DNA is common to all life on Earth, and the code is almost identical in all organisms.
This suggests that all organisms alive today are related and that DNA was inherited
from a common ancestor.
Darwin hypothesized that natural selection led to the different beak shapes in the Galapagos
finches. Describe how the Grants tested this hypothesis. Did their data support Darwin’s
The Grants measured all the beaks of the medium ground finch. They recorded the
survival of different birds and continued the study for many years. The Grants showed
that natural selection is occurring often and more rapidly than many thought possible.
Use the illustration below to answer question 25.
Based on what you can see, are the brown mice or white mice better adapted to their
environment? Explain why.
The environment of the mice looks brown, so the brown mice are better adapted. Brown
mice will blend in better to their environment and be harder for predators to see.
Compare and contrast the processes of artificial and natural selection.
Both artificial and natural selection changes the heritable traits of a population or
species over time. In both cases, organisms with certain traits are most likely to
survive and reproduce than organisms with other traits. In artificial selection, a
breeder or farmer decides which organisms reproduce. In natural selection,
environmental conditions determine which organisms reproduce.
Use the following information to answer questions 27—29.
Hawaiian honeycreepers like the i’iwi have a lot in common with the Galapagos finches. Like the
finches, the honey creepers are small birds found nowhere else on Earth. They live on islands far from
the mainland. And like the finches, the 20 known species of honeycreepers are closely related to one
another. This suggests the honeycreepers are all descended, with modification, from a common
ancestor that arrived on the islands between 3 and 4 million years ago.
Imagine a small group of birds landed on one of the Hawaiian Islands millions of years ago. This
small population then reproduced. Do you think all of the descendants would have stayed on that
one island? Explain your answer.
No, because most species tend to overproduce, the island would soon become
overcrowded. This would be especially true in the Hawaiian Islands because of a lack
of predators like snakes, cats, and rats). Because of overcrowding, some birds would
leave to escape competition.
Do you think that environmental conditions are the same everywhere on all of the Hawaiian
Islands? How might the environment have affected the evolution of the honeycreepers?
Environmental conditions vary from island to island. On a single island, the
environment is different in the lowlands than in the mountains. Birds might evolve
adaptations to thrive in one of the different environments.
Explain how the different species of honeycreepers in Hawaii today might have evolved from one
ancestral species.
A population of migrating birds might have been blown to the islands during a storm.
The birds would naturally have had heritable variations. Competition and different
environments would make it easier for birds with certain traits to survive. These birds
would become more common. Eventually birds flew to other islands, where the
process of evolution by natural selection continued.
List one misconception people have about evolution and explain why it is a mistaken belief.
Evolution is a theory about the origin of life
o The theory of evolution primarily deals with the manner in which life has
changed after its origin. While science is interested in the origins of life (for
example the composition of the primeval “soup” from which life might have
come) but these are not issues covered in the area of evolution. What is known
is that regardless of the start, at some point life began to branch off. Evolution
is, therefore, dedicated to the study of those processes.
Organisms are always getting better
o Many organisms like fungi, sharks, crayfish, and mosses have remained
essentially the same over a great period of time. These organisms are all
sufficiently adapted to their environment to survive without further
Other taxa changed a lot in order to adapt to different environmental
conditions and exploit new niches. The cat family is one example, which
includes such diverse members as the tiger, lion, leopard, puma, lynx, and
house cat. On-the-other hand, some creatures like mammoths have had their
environments change so quickly that their adaptations may not be as well
suited to their new situation. Fitness is linked to their environment, not to
Evolution means that life changed ‘by chance’
o In fact, natural selection is not random, but the mutations natural selection
acts upon are. Many aquatic animals need speed to survive and reproduce –
creatures with mutations which provide that ability are more suited to their
environment and are more likely to survive natural selection. In turn, they
will produce more offspring with the same traits and the cycle continues. The
idea that evolution occurs by chance does not take the entire picture in to
Natural selection involves organisms ‘trying’ to adapt
o Organisms do not “try” to adapt – it is natural selection that enables various
members of a group to survive and reproduce. Genetic adaptation is entirely
outside of the power of the developing organism.
Natural selection gives organisms what they ‘need.’
o Natural selection has no “intelligence” – it cannot tell what a species needs. If a
population has genetic variants that are more suited to their environment,
they will reproduce more and the population will evolve. If a genetic variant is
not present, the population might still survive but with little evolutionary
Evolution is ‘just’ a theory
o Scientifically speaking, a theory is a well substantiated idea that explains
aspects of the natural world. Unfortunately other definitions of theory (such
as a “guess” or a “hunch”) cause a great deal of confusion in the non-scientific
world when dealing with the sciences. They are, in fact, two very different
Evolution is a Theory in Crisis
o There is no debate in science as to whether or not evolution occurred – there
is, however, debate over how it happened. The finer points of the process are
vigorously debated which can cause people to believe that the theory is in
crisis. Evolution is sound science and is treated as such by scientists
Gaps in the Fossil Record Disprove Evolution (i.e., there are no transitional fossils)
o Actually, thousands of transitional fossils exist – for example, there are fossils
of transitional organisms between modern birds and their dinosaur
ancestors, as well as whales and their land mammal ancestors. There are
many transitional forms that have not been preserved, but that is simply
because some organisms do not fossilize well or exist in conditions that do not
allow for the process of fossilization. Science predicts that there will be gaps
in the record for many evolutionary changes. This does not disprove the
Evolutionary Theory is Incomplete
o Evolutionary science is a work in progress. Science is constantly making new
discoveries with regard to it and explanations are always adjusted if
necessary. Evolutionary theory is like all of the other sciences in this respect.
Science is always trying to improve our knowledge. At present, evolution is
the only well-supported natural explanation for all of life’s diversity.
The Theory is Flawed
o Science is an extremely competitive field – if any flaws were discovered in
evolutionary theory they would be quickly corrected. All of the alleged flaws
that contrarians have put forth have been investigated careful by scientists
and they simply do not hold water. They are usually based on
misunderstandings of the theory or misrepresentation of the evidence.
Evolution is not science because it is not observable
o Evolution is observable and testable. The confusion here is that people think
science is limited to experiments in laboratories by white-coated technicians.
In fact, a large amount of scientific information is gathered from the real
world. Astronomers can obviously not physically touch the objects they study
(for example stars and galaxies), yet a great deal of knowledge can be gained
through multiple lines of study. This is true also of evolution. It is also true
that there are many mechanisms of evolution that can be, and are studied
through direct experimentation as with other sciences.
Most Biologists have rejected Darwinism
o Scientists do not reject Darwin’s theories, they have modified it over time as
more knowledge has been discovered. Darwin considered that evolution
proceeds at a deliberate, slow pace – but in fact it has now been discovered
that it can proceed at a rapid pace under some circumstances. There has not
been, so far, a credible challenge to the basic principles of Darwin’s theory.
Scientists have improved and expanded on Darwin’s original theory of natural
selection – it has not been rejected, it has been added to.
Evolution Leads to Immoral Behavior
o All animal species have a set of behaviors that they share with other members
of their species. Slugs act like slugs, dogs act like dogs, and humans act like
humans. It is preposterous to presume that a child will begin to behave like
another creature when they discover that they are related to them. Evolution
is a biological process. It is nonsensical to link evolution to immoral or
inappropriate behavior.
Evolution Supports “Might Makes Right”
o In the 19th and early 20th century, a philosophy called “Social Darwinism” sprung
up from misguided attempts to apply biological evolution to society. This
philosophy said that society should allow the weak to fail and die, and that not
only is this an ideal situation, but a morally right one. This enabled prejudices to
be rationalized and ideas such as the poor deserved their situation due to being
less fit were very popular. This was a misappropriation of science. Social
Darwinism has, thankfully, been repudiated. Biological evolution has not.
Teachers Should Teach Both Sides
o There are tens of thousands of different religious views concerning creation. It is
simply impossible for all of these views to be presented. Furthermore, none of the
theories are based in science and therefore have no place in a science classroom.
In a science class, students can debate where a creature branched off in the tree of
life, but it is not right to argue a religious belief in a science class. The “fairness”
argument is often used by groups attempting to inject their religious dogmas in to
the scientific curricula.
If we evolved from monkeys, then why are there still monkeys?
o This is actually a very common misunderstanding about the theory of evolution.
The theory is not that humans came from monkeys, but that humans evolved from
an earlier species which Monkeys also evolved from. Monkeys are not our
ancesors, but our cousins--both humans and monkeys (and apes) evolved from a
species that was neither human or monkey (or ape).
If evolution were true, why don’t we see something like a crocoduck?
o If a crocoduck did exist, it would disprove evolution, not support it. The theory of
evolution does not state that a crocodile has to become a duck, or vice-versa, or
that such a thing must have happened for evolution to be correct. Even if a duck
were supposed to have evolved directly into a crocodile, nothing says that a duck
would have a crocodile head.
An intermediate form between a duck and a crocodile is not predicted by
evolution because birds and crocodiles are only distantly related. Birds evolved
out of an animal similar to Archaeopteryx while crocodiles evolved out of
different types of reptiles called archaeosaurs more than 50 million years earlier.
Intermediate fossil forms between the birds and their ancestors have been found
as have intermediate fossils between the crocodiles and their different ancestors.
The crocoduck fallacy demonstrates a complete lack of understanding of
biological evolution. This kind of thinking requires a direct, single-step ancestor
between every two species on the planet. In other words, there must have been
not only a crocoduck, but also a croco-beaver and a beaver-duck predating the
crocodile, beaver, and duck.