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Lesson 48 of 84 · Genetics
ExperimentThe Fossil Record and Evolution (Part 3)
What You'll Learn
The fossil record provides evidence for evolution by showing how organisms have changed over time. Transitional fossils show features of both ancestral and descendant species.
Key Words
- dominant
- recessive
Materials Needed
- onion skin
- iodine stain
- paper
- colored pencils
- coins (for Punnett squares)
Safety First
- Do not taste any materials.
- Wear safety goggles when mixing liquids.
Steps
Step 1 — Read
Study the diagram and label the parts you recognize.
Step 2 — Do
Extract DNA from a strawberry using dish soap, salt, water, and rubbing alcohol. Observe the stringy white substance—that's DNA!
Step 3 — Observe
Use your senses (except taste) to describe what you notice.
Step 4 — Record
Write a summary of your findings in 3-5 sentences.
Check Your Understanding
Question 1
1 of 3What provides evidence for evolution?