Evolution Unit Test: Practice Guide Answers
Part A: Complete the following questions:
1.) What is fitness? How is it measured? How many fertile offspring it produces
2.) What is a representative organism? When studying fossils found in rock layers,
what type of information can be deciphered? One that serves as an example or type for
others of the same classification. Oldest organisms are located on the bottom.
3.) How do different variations of species arise? Mutations and gene [allele]
recombinations.
4.) What occurs when gene frequencies of a population change? Populations change
[evolve] What if they stay the same? No change, equilibrium How does this happen?
Change could be due to natural selection, genetic drift, or gene flow]
5.) What is punctuated equilibrium? Give an example. Some species undergo long
periods of stability interrupted by geologically brief periods of significant change.
During these brief periods, new species may evolve.
6.) What is gradualism? Give an example. Many small changes occur over a large period of
time
7.) What is embryology? Why is studying embryos important to the modern theory of
Evolution? The study of embryos and their development. There are similarities in the
developmental stages of vertebrate organisms in the animal kingdom.
8.) What is the founder effect? What does it result in? The movement of new genes into a
population as a result of migration or hybridization. A new population.
9.) What is gene flow? What does it result in? Gene flow—also called migration—is any
movement of genes from one population to another. It results in migration. [Genetic
variation].
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10.)
What is a population bottleneck? What does it result in? It is an event that
drastically reduces the size of a population. The bottleneck may be caused by various
events, such as an environmental disaster, the hunting of a species to the point of
extinction, or habitat destruction that results in the deaths of organisms. Genetic drift
acts more quickly to reduce genetic variation in small populations, undergoing a
bottleneck can reduce a population’s genetic variation.
11.)
What factors affect genetic diversity? Adaptations to environment
12.)
What factors contribute to a change in the allele frequency of a population?
Mutations and sexual reproduction
13.)
What is the difference between geographic isolation and reproductive
isolation? What can each result in? Geographic isolation refers to the separation of two
populations by physical boundaries, such as rivers, mountains, etc. Reproductive
isolation occurs when two populations no longer produce viable offspring. This can be
due to geographical isolation or other factors such as behavioral differences.
14.)
How were so many different types of finches able to survive on the Galapagos
Islands? Birds adapting to different island environments
15.)
What is natural selection? What does it act on? What does it result in? Natural
selection acts on individuals, which in turn may result in the evolution of populations
over time.
16.)
Describe the illustration below in a complete sentence. What process is
occurring? The evolution of the horse occurred over a period of 50 million years,
transforming the small, dog-sized, forest-dwelling Eohippus into the modern horse
Equus. Evolution!
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17.)
What is adaptive radiation? Give an example. Biologists have found more
than 500 species of fruit flies on various Hawaiian Islands, all of them coming
from a single ancestor species.
18.)
How are mutations related to Evolution? How do they occur? Mutations can
be considered as one of the raw materials of evolution because they contribute
to new variations in organisms.
19.) Why are fossils an integral piece of evidence for the modern theory of Evolution?
Organisms on Earth have evolved and changed significantly over time.
20.) What is a homologous structure? Give an example. Similar [Same] structures, but
different functions, and likely evolved from the same distant ancestor. The leg of a cat and
the wing of a bat.
21.) What is an analogous structure? Give an example. Different structures. The wing of an
insect and the wing of a bat.
22.) What is a vestigial structure? Give an example. Structures that no longer have any
function. The human appendix.
23.)What are the five pieces of evidence for Evolution?
1. Fossils
2. Homologous Structures
3. Vestigial Structures
4. Embryology
5. Biochemistry- more genes/proteins in common means organisms are more
closely related.
24.)Who is Charles Darwin? A naturalist, known for his contributions to evolutionary
theory. Why is he important to the Theory of Evolution? Natural Selection acts Genotypes
Part B: Use the table to fill in the cladogram below:
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25.)
Salamander
Horse
Pig
Chimpanzee
2
h
i
m
p
a
n
z
e
e
0
h
i
m
p
a
n
z
e
e
Time
27
Chi
mp
anz
ee
14
Chi
mp
anz
ee
Humans
C
h
i
C
m
Part C: Answer the following questions concerning the study on clam
h shell color.
p
i
26.)A population containing spotted and unspotted clams has surfaced on the shoesa of New
m The seagulls
Jersey. The seagulls break the clams open by dropping them onto rock jetty.
eat
n
p
the bodies of the clams and leaves the shells. Researchers have counted the number
z of live
a
clams and broken clam shells. The data is below.
e
n
e
Spotted Shells
z Unspotted Shells
Living Clams
150
165
e
e
Broken Shells (dead clams)
387
212
79
a.)Which clam is more likely to get caught? Spotted shell Why? 387 are dead
b.)How will allele frequencies change over time? More unspotted shells
c.)Which allele is favored? More unspotted shells Why? They are living
d.)Which allele does natural selection work against? Spotted shell Why? They are dead
Good Luck Studying!!!!!
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