Evidence Island
Welcome to Evidence Island!
While you are on this island, your objectives are to
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Understand and explain how homologous structures are evidence of evolution
Explain how embryonic development is used as evidence of evolution
Explain how similarities in DNA are used to explain relationships between species
Explain how similarities in DNA are used to explain relationships between species
Key Terms: homologous, embryonic
At Home Tasks
Text p. 149-152. Q. 1b, 1c Q. 2c p. 153
Required Tasks for Evidence Island
Task 1: DNA Evidence: It’s Molecular Time
Task 2: Embryology Evidence: Similarities in Embryology
Task 3: Lab Activity: Homologous Structures
Evidence Island
Required Tasks for Evidence Island
Task 1: DNA Evidence: It’s Molecular Time
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Read “It’s Molecular Time.”
Cut out the DNA sequences. Glue or tape into your journal starting with living
humans and ending with the most distant ancestor
Assume the rate of mutation is one difference for every 100,000 years. What is
the age of the oldest ancestor?
Task 2: Embryology Evidence: Similarities in Embryology
a. With a partner, discuss the embryos on p. 149 of your text. What similarities and
differences do you see
b. Discuss the embryos shown in the figure below. How are they evidence of
evolution? Record your reflection in your journal
Task 3: Lab Activity: Homologous Structures
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Complete the skills Activity on page 150 with a partner. Do you think that crocodiles
share a common ancestor with birds, dolphins, and dogs? Support your answer with
evidence
Examine the X rays to look for evidence of homologous structures. Select two or three.
Sketch and compare/contrast the structures. Label the names of the bones in your
sketches.
Evidence Island
Optional Activities for Evidence Island
Task 1: LAB
Perform the lab “Tell Tale Molecules” on page 154 of the text. Answer all lab questions in your
journal
Task 2: Interpreting Diagrams
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Complete the interactive “Guess the Embyro” found at tinyurl.com/acel554
Was this activity difficult? Why or why not?
What did you observe?
Task 3: Research on Vestigial Structures
a. Complete the chart of human vestigial structures. Use the internet to help you find
the answers
b. Paste the chart into your journal
c. Explain how vestigial structures can be used as evidence for evolution
Task 3: Writing Activity: Embryology
Write a one paragraph persuasive essay using embryology to support the theory of evolution.
Task 4: Data Interpretation
a. Read “Mutations Up Close” (at Evidence Island) and complete the directions
b. What does the DNA sequence tell you about humans and chimps?
Task 5: Reading: How Snakes Lost Their Legs
Use information from the text to explain how snakes have changed over time