Activity worksheet (Modified)
Constructing CLADOGRAMS
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IIIII-
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Sets
Objectives:
 Given some groups of organisms and some of their distinguishing characteristics, you will construct a cladogram to
infer evolutionary relatedness.
Materials: Factsheet, manila paper, pentel pen and activity sheet.
Procedure:
 Step 1. Using the explanations below, you can determine what characteristics each animal has. In the Data Table
provided (on your Cladogram Worksheet.)
Explanations of Characteristics:
Set #1: Dorsal nerve cord (running along the back or "dorsal" body surface) Notochord (a flexible but supporting cartilage-like
rod running along the back or "dorsal" surface) s
Set #2: Paired appendages (legs, arms, wings, fins, flippers, antennae) Vertebral column ("backbone")
Set #3: Paired legs set
Set #4: Amnion (a membrane that holds in the amniotic fluid surrounding the embryo; may or may not be inside an egg shell)
Set #5: Mammary glands (milk-secreting glands that nourish the young)
Set #6: Placenta (structure attached to inside of uterus of mother, and joined to the embryo by the umbilical cord; provides
nourishment and oxygen to the embryo)
Set #7: Canine teeth short (same length as other teeth) Foramen magnum forward (spinal cord opening, located forward,
under skull)
Traits
Set 1
Dorsal Nerve cord
Notochord
Set 2 Paired
Appendages
Set 3 Paired legs
Set 4 Amnion
(Amniotic sac)
Set 5 Mammary Glands
Set 6 Placenta
Set 7 Canine
Teeth
short
Foremen magnum
fwd
TOTALS OFXs…>
Questions:
Kangaroo
X
Lamprey
x
ORGANISM
Rhesus
Monkey
x
Bullfrog
Human
Tuna
x
Snapping
Turtle
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
X
X
X
5
1
6
X
X
x
3
Which of the organism has the most shared derived character?
Human
Which of the organism has the least?
Lamprey
Which of the character or traits that most of the organism shared?
Dorsal Nerve cord Notochord
X
7
4
2
Step 2: Use the table as reference in constructing a cladogram to illustrate the ancestry of the animals.
The diagram should reflect shared characteristics as time proceeds. An example is shown below. Notice how the different
animals are all at the same time level (across the top) since they all live today.
Example of Cladogram
Questions:
Which of the animals is the recent ancestor?
Human
Which of the organism that closely related to one another?
Human, kangaroo, tuna, snapping turtle, rhesus monkey and Bullfrog
Which of the organism show most distantly related?
Lamprey
Cladogram Worksheet
Step 1:
Sets
Traits
Set 1
Dorsal Nerve cord
Notochord
Paired
Appendages
Paired legs
Amnion
(Amniotic sac)
Mammary Glands
Placenta
Canine
Teeth
short
Foremen magnum
fwd
TOTALS OFXs…>
Set 2
Set 3
Set 4
Set 5
Set 6
Set 7
Kangaroo
Step 2: Construct a cladogram
X
Lamprey
x
ORGANISM
Rhesus
Monkey
x
Bullfrog
Human
Kangaroo
x
Snapping
Turtle
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
X
X
X
5
1
6
X
X
X
x
3
7
4
2
Posing Question:
1. Why does cladogram constructed?
Cladogram is being constructed because it is widely useful in inferring the relationship of the organism. Cladogram shows
pattern of ancestry in which it can depict the relatedness of the organism as to how what characters that they shared. In
addition, cladogram show what organism ancestor and recent one because it show how the different animals are all at the
same time level related since they all live today.
2. How do we construct a cladogram?
The cladogram are being constructed based from their shared derived character because shared derived character provides
information on the phylogeny of the organism. In constructing a cladogram also you select animals and their shared derived
character that you want to infer relatedness. Next you will create a table so that you can identify what organism has the most
shared and the least shared organism. Lastly you can now construct a cladogram by using the table as your reference in
constructing a cladogram
Reference:
(Evolution & the Nature of Science Institutes)www.indiana.edu/~ensiweb
http://www.ucmp.berkeley.edu/clad/clad4.html