Activity 3
Activity Title: Evidence of Evolution
Learning Objectives:
1. Describe how fossil records, comparative anatomy, embryologic
development, and genetic information provide evidence for evolution
Part A: Where Do I Belong?
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1. Which is assumed to be
the oldest organism?
Why do you think so?
What is the probable
age of the fossil?
2. In what era can you
possibly find the most
recent fossil? Why do
you say so?
3. Do you think there are
organisms that lived
during the Cambrian
Period? Explain your
answer.
4. When do you think did
the present-day humans
first appeared on earth?
5. Describe how organisms
are arranged in the
table.
Part B: Analogous!
Homologous!
Write in the space provided
H if the structures below
are homologous
and A if they are
analogous.
6. Can you say that
human, whale and bat
might belong to a common
ancestral group? Explain
why.
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Part C: Who is My Relative?
Study and compare the stages of embryonic development of the different vertebrates.
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7. In what stages of development
of the organisms above show
similarities?
8. What structures are similar in
Stage
1
of
embryonic
development of the organisms?
9. In stage 3, identify the
structures
that
made
the
organisms differ from each other.
10. Can embryonic development
be a piece of evidence that
evolution took place? Explain.
Part D: Let’s Compare
Examine the amino acid data below and list the amino acid differences of the organisms compared to
human amino acid sequence in the next table. Answer the following questions.
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Organism
Chimpanzee
Gorilla
Rhesus Monkey
Horse
Kangaroo
Amino acid Difference
none
LYS
GLN, LYS
ALA, ALA, LEU, VAL, ARG
LYS, LYS, ILE, ILE, ILE, CYS, GLU
No. of Amino Acid Difference
0
1
2
5
7
11. Based on the activity, which organism is closely related to humans? Why?
12. Which organism is least related to humans? Why?
Answer Key
Part A: Where Do I Belong?
1. Which is assumed to be the oldest organism? Why do you think so? What is the probable age
of the fossil?
-The oldest organism in the list are the trilobites, (answers may vary). They lived during
Paleozoic Era, in the Silurian and Ordovician period. They can be 600 million years old.
2. In what era can you possibly find the most recent fossil? Why do you say so?
-Cenozoic Era, the recent fossil may be found in the uppermost layer of the rock. (Answers
may vary).
3. Do you think there are organisms that lived during the Cambrian Period? Explain your answer.
-Yes. Rock layers in the Cambrian period also have traces /imprints of mollusks that lived
during that time. Most of them were invertebrates.
4. When do you think did the present-day humans first appeared on earth?
-Cenozoic Era,
5. Describe how organisms are arranged in the table.
-they are arranged according to their age. Specifically, from the oldest to the most recent.
Part B: Analogous! Homologous!
Write in the space provided H if the structures below are homologous and A if they are analogous.
Structures
Classification
Human arm and Whale flipper
H
Whale Flipper and Alligator forelimb
H
Bat wing and butterfly wing
A
Bird wing and butterfly wing
A
6. Can you say that human, whale and bat might belong to a common
ancestral group? Explain why.
- Yes, because their forelimbs are made up of same kinds of bones that just vary in size and function
differently, suggest that they share a common
Part C: Who is My Relative?
Study and compare the stages of embryonic development of the different vertebrates.
7. In what stages of development of the organisms above show similarities?
- The first and second stages of development of the organisms show better similarities.
8. What structures are similar in Stage 1 of embryonic development of the organisms?
- shape of head, lower body parts, forelimbs
9. In stage 3, identify the structures that made the organisms differ from each other.
- their size, shape of head, hind limbs, eye structure
10. Can embryonic development be a piece of evidence that evolution took place? Explain.
-yes, because similarities in structures may suggest that organisms share common ancestors.
Part D: Let’s Compare
Organism
Chimpanzee
Gorilla
Rhesus Monkey
Horse
Kangaroo
Amino acid Difference
none
LYS
GLN, LYS
ALA, ALA, LEU, VAL, ARG
LYS, LYS, ILE, ILE, ILE, CYS, GLU
No. of Amino Acid Difference
0
1
2
5
7
11. Based on the activity, which organism is closely related to humans? Why?
-Chimpanzee because it has similar amino acid sequence to humans
12. Which organism is least related to humans? Why?
- Kangaroo because it has the highest number of different amino acids compared to humans.