EVOLUTION STUDY GUIDE
True or False: If the statement is true, write “true" If it is false, change the
underlined word or words to make the statement true.
1. A predator is a trait that helps an organism survive and reproduce itself
in its environment. adaptation
2. A variation is an error that occurs when DNA is copied. mutation
3. A fossil is the preserved remains of a once-living species.
true
4. A species becomes preserved when it no longer lives on Earth.
extinct
5. Two structures are homologous if they have the same function but did
not evolve in the same way. analogous
6. Natural Selection is sometimes described as survival of the fittest.
_______true____
Multiple Choice: Choose the letter of the response that correctly answers
the question.
7. Why were the Galapagos Islands a good place in which to study
adaptations?
a. T h e y were close to one another yet had different climates
b. They were close to one another and had nearly identical climates
and plants
c. T h e y were located close to Darwin's home
d. T h e y were well-known as good places to study organisms
8. Organisms that are said to be more "fit" than others have which of the
following?
a. Mutations
c. More offspring
b. F a v o r a b l e variations
d. Analogous structures
9. Who established the basis of the modern theory of why things evolved?
a. Donald Johanson
b. Charles Darwin
c. Louis Leakey
d. Raymond Dart
10. What type of scientist uses fossils to study forms of life that
existed in prehistoric times?
a. Archaeologist
c. Paleontologist
b. B o t a n i s t
d. Scientologist
11. What kind of dating of a fossil looks at the amount of a certain element
in the fossil?
a. Relative
c. Reactive
b. R a d i o a c t i v e
d. Radar
12. Humans evolved from ________________________________
a. Monkeys
c. Primates
b. L e m u r s
d. Gibbons
13. What is the name for an adaptation that causes a prey species to look
like a different organism or object?
a. Camouflage
c. Mimicry
b. Warning colors
d. Protective covering
14. The study that looks at the earliest stages of growth and development
in organisms is known as:
a. Growthology
b. Embryology
c. Scientology
d. Biology
15. A bird and a butterfly both have wings, but they are not related. What
do we call these structures?
a. Homologous structures
b. Analogous structures
c. V e s t i g i a l structures
16. The limb of a cat and the limb of a horse show similar bone structure.
These structures are an example of:
a. Homologous structures
b. Analogous structures
c. V e s t i g i a l structure
Short Answer: Answer each of the following in a sentence or brief paragraph.
17. Name 3 examples of vestigial structures?
Appendix, tailbone, wisdom teeth, nictitating membrane (eyes)
18. Explain how fossils can tell us the behavior of an organism.
Fossils are a record of evolution & extinction, natural selection changed
species over time, and behavior is shaped by natural selection
19. How might an adaptation help an organism survive in a cold environment?
An adaptation is a feature that is common in a population because it
provides some improved function. Thus fur could aid in maintaining
temperature in a cold environment.
20. Identify the causes of variations within a population of organisms.
Mutation, recombination in sexual reproduction, and lateral gene transfer
21. Explain how vestigial structures can be used to support evolution.
Vestigial structures provide a clue to the evolutionary history of a species
because they are remnants of structures found in the ancestral species.
Vestigial refers to an organ or part (for example, the human appendix) which
is greatly reduced from the original ancestral form and is no
longer functional or is of reduced or altered function.
22. An antibiotic is a drug that is used to kill bacterial cells. Using
your knowledge of survival of the fittest, why do you think some
bacterial diseases are no longer controlled by antibiotics? The
bacterial diseases have built up a resistance to the antibiotics – by
swapping DNA with each other, thereby prohibiting the bacterial
cells from being destroyed by the antibiotics – lateral gene
transfer
23. The Saddleback tortoise developed adaptations, such as a long neck
and open shell, to help it reach higher plants. What adaptations might a
tortoise that must find food in water develop? Webbed feet for
swimming
24. Explain Darwin's theory of natural selection in your own words.
Variation in traits – green/brown beetles
Differential reproduction – green beetles get eaten by birds more readily
than brown, therefore their survival rate is lower & they reproduce less
hereditary – brown beetles produce brown beetles, thus the brown beetle
becomes more prevalent
25. Explain how Darwin's finches displayed natural selection.
The shape of their beaks adapted to drought conditions, finch
population developed deeper, stronger beaks enabling them to eat
tougher seeds
26. What is a gene pool?
The combined genetic information of all members of a particular population
27. What is allele frequency?
The number of times an allele occurs in a gene pool compared to other
alleles. Ex: green eyes vs. brown eyes
28. In genetic terms, how does evolution occur?
Evolution is a change in allele frequency of the gene pool
29. What is a mutation? What causes mutations?
 Any change in a sequence of DNA
 Causes – because of mistakes in the replication of DNA or as a
result of radiation or chemicals in the environment
 Only gamete (occurs in sperm/egg) mutation affect evolution
30. How does natural selection affect single gene traits?
Lead to changes in allele frequency, dramatic shifts, or no change at all Ex:
dimples shift to no dimples
31. What is directional selection?
Individuals at one end of the curve have higher fitness than individuals in the
middle or at the other end. The whole range will shift in that direction.
32. What is stabilizing selection?
Individuals near the center of the curve have higher fitness than individuals
in the middle or at the other end. Average becomes more common. Ex: birth
weight
33. What is disrupted selection?
Individuals at the upper & lower ends of the curve have higher fitness than
individuals near the middle – can create 2 distinct variations Ex: too little
iron – too much iron (bubonic plaque)
34. What is genetic drift?
Random change in allele frequencies in small populations. Each generation
by chance leaves a few more descendants behind than others. The genes
will be the “lucky” left behind – not necessarily the “better” genes.
35. What is the Founder effect?
Allele frequencies change as a result of the migration of a small subgroup
of a population. Individuals colonize a new habitat, only their genes will be
seen in new population – type of genetic drift
36. What is geographical isolation?
A common way for speciation to begin – rivers change course, mountains
rise, continents drift, organisms migrate & what once was a continuous
population is divided into 2 or more smaller populations. Ex: squirrels
(Grand Canyon)
37. What is temporal isolation?
Time – when species reproduce at different times Ex: crabs
38. What is behavioral isolation?
Occurs when populations are capable of interbreeding but have
differences in courtship rituals or other types of behavior Ex: birds
39. What is genetic equilibrium?
A condition where a gene pool is not changing in frequency because the
evolutionary forces acting upon the allele are equal, thus, resulting in
a population to not evolve even after several generations.
40. What are the conditions that must be met to achieve genetic
equilibrium?
 Random mating
 Very large population
 No movement into or out of the population
 No mutations
 No natural selection
41. How did the Finches get to the Galapagos Islands?
Flew or were blown to the island – A small bird that doesn’t usually fly over
open H2O it is thought they got lost or blew off course by a storm
42. How did new species of finches come about on the islands?
Through adaptation to the environments, one species developed larger
beaks for survival purposes. Finches mate with birds that have the same size
beak as they have. This caused reproductive isolation. Therefore isolation on
different islands, genetic change & reproductive isolation repeated this process
to eventually produce 13 different finch species.
43. What are the principles that led to the origin of new species of
finches on the islands?
 Separation of populations
 Genetic change
 Reproductive isolation
 Ecological competition
 Continued evolution