Download Evidence of Evolution2013

Evidence of Evolution
Background
When Charles Darwin first proposed the idea that all new species descend from an ancestor, he performed an
exhaustive amount of research to provide as much evidence as possible. Today, the major pieces of evidence for this
theory can be broken down into the fossil record, embryology, comparative anatomy, and molecular biology.
Comparative Anatomy
Shown below are images of the skeletal structure of the front limbs of 6 animals: human, crocodile, whale, cat,
bird, and bat. Each animal has a similar set of bones. Color code each of the bones according to this key:
Humerus [ ]
Ulna
[ ]
Radius
[ ]
Carpals
Metacarpals
Phalanges
[ ]
[ ]
[ ]
Name: ___________________________ Class: ______________________ Date: ____________________
For each animal from the previous page, indicate what type of movement each limb is responsible for.
Animal
Primary Functions
Human
Using tools, picking up and holding objects
Whale
Cat
Bat
Bird
Crocodile
Questions:
1. How are these structures similar?
2. Why are they considered homologous structures?
Compare the anatomy of the butterfly and bird wing below.
Questions:
1. What is the function of each of these structures?
2. How are they different in form/structure? Give specific differences.
Name: ___________________________ Class: ______________________ Date: ____________________
Compare the overall body structure of the cave fish and the minnow below.
Questions:
1. What is the biggest, most obvious difference between the body structure of these two fish?
2. Assume the two fish came from the same original ancestor. Why might the cave fish have evolved
without eyesight?
You have now studied three different types of anatomical structures:

Homologous structures show individual variations on a common anatomical theme. These are seen
in organisms that are closely related.
1. Give an example of a homologous structure from this activity: ________________________________

Analogous structures have very different anatomies but similar functions. These are seen in
organisms that are not necessarily closely related, but live in similar environments and have similar
adaptations.
2. Give an example of an analogous structure from this activity: ________________________________

Vestigial structures are anatomical remnants that were important in the organism’s ancestors, but
are no longer used in the same way.
3. Give an example of a vestigial structure from this activity: ___________________________________
Name: ___________________________ Class: ______________________ Date: ____________________
Molecular Biology
Molecular Biology
Below is a list of the amino acids in part of a cytochrome protein molecule for 9 different animals. The more sequences that are similar the more
related the organisms are at the molecular level.
Directions: For each non-human animal, take a highlighter and mark any amino acids that are different than the human sequence. When you finish,
record how many differences you found in the last portion of the table labeled “Number of Amino Acid Difference Compared to Human”
Human
Chicken
Horse
Tuna
Frog
Shark
Turtle
Monkey
Rabbit
42
Q
Q
Q
Q
Q
Q
Q
Q
Q
43
A
A
A
A
A
A
A
A
A
44 46 47
P Y S
E F S
P F T
E Y S
A F S
Q F S
E F S
P Y S
V F S
49
T
T
T
T
T
T
T
T
T
50
A
D
D
D
D
D
E
A
D
53
K
K
K
K
K
K
K
K
K
54
N
N
N
S
N
S
N
N
N
55
K
K
K
K
K
K
K
K
K
56
G
G
G
G
G
G
G
G
G
57
I
I
I
I
I
I
I
I
I
58
I
T
T
V
T
T
T
T
T
60
G
K
G
N
G
Q
G
G
G
61
E
E
E
N
E
Q
E
E
E
62
D
E
D
D
D
E
E
D
D
Sequence continued from above…
Number of Amino Acid Differences Compared to
Human
65
66
100
101 102 103 104
M
M
M
M
M
R
M
E
E
E
E
E
I
E
K
K
D
S
S
K
D
A
A
A
A
A
T
A
T
T
T
T
C
A
T
N
N
S
S
S
A
S
E
E
K
K
S
K
Human
Chicken
Horse
Tuna
Frog
Shark
Turtle
M
E
K
A
T
N
E
Monkey
M
E
K
A
T
N
E
Rabbit
63
T
T
T
T
T
T
T
T
T
64
L
L
L
L
L
L
L
L
L
Questions:
1. Based on the Cytochrome C data from the previous page, which organism is most closely related to
humans?
2. Which organism(s) is the least related to humans?
3. Two organisms look very similar but their sequence of amino acids are very different from one
another. What does this tell you about the importance of molecular biology when determining
relationships between organisms?
Directions: Complete the table below by checking the correct column for each description
Description
Modified structure seen among
different groups of descendants
(the offspring of several
generations)
Eyes absent/nonfunctioning in
blind cave dwelling salamanders
DNA and RNA comparisons that
might indicate evolutionary
relationships
Sharks having a structure made
of cartilage while dolphins have
a structure made of bones
A body structure that is no
longer used for its original
function but that might have
been used in an ancestor
Homologous Analogous Vestigial Comparative
Structure
Structure Structure Biochemistry
Name: ___________________________ Class: ______________________ Date: ____________________
Convergent vs. Divergent Evolution
Are these animals convergent
or divergent? Explain.
Questions:
1. Explain how organisms can display convergent evolution in nature.
2. Explain how organisms can display divergent evolution in nature.
3. Between convergent and divergent, which would lead itself to speciation (the evolution
of a new species)?
A phylogenic tree is a diagram showing the evolutionary history of an animal. The image above is a
phylogenic tree of various protists.
Questions:
1. Which three organisms labeled above are most related based on the phylogenic tree?
2. Which organisms are more related E and D or F and G? Explain.
3. Are all of these organisms related to one another?
4. Is a phylogenic tree an example of convergent or divergent evolution?
Name: ___________________________ Class: ______________________ Date: ____________________
Questions:
1. Looking at the figure to the left, which moth would
survive if pollution increased? Explain.
2. Would the moth that is trying to survive be able to
change its pigment to blend in better?
3. How would its population increase over time?
Figure A
Figure B
Questions:
1. Describe the difference between Figure A and Figure B
2. In which figure does speciation take place gradually?
3. In which figure does speciation occur in “spurts”?
4. What type of evolution is occurring in Figure A?
5. What type of evolution is occurring in Figure B?
6. Are these figures an example of convergent or divergent evolution?