Lesson 11 of 11 · Earth Systems
Experiment⭐ 30 XP🌋 Rock RealmWhat Fossils Cannot Tell Us
Earth Systems.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Weather isn't random — it's just complicated.
Mind = Blown
🌊 The deepest part of the ocean is deeper than Mount Everest is tall.
Make a hypothesis first
Before you observe: what shape will it leave?
What You'll Learn
Fossils preserve hard parts far more often than soft ones, and only in the right kind of sediment. The record is therefore patchy: an animal missing from the rocks may simply never have been fossilised.
Key Words
Tap a word to see its definition.
Materials Needed
- modelling clay
- shells
- leaves
- sponge
Safety First
- Wash hands after handling clay and do not put shells near your mouth.
Steps
Read the explanation above and note the two key terms before you start.
Press shells, leaves and a piece of sponge into clay, then compare how clear each impression is. Use the result to explain why jellyfish fossils are so much rarer than shell fossils.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2Fossils most often preserve:
Where you see this in real life
This is shaping the ground you walk on, slowly, every single day.
Stretch Challenge
Try this in real life this week.
Find a rock outside and try to guess how old it is.
For the dinner table
“What's the slowest change you can think of?”
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What Fossils Cannot Tell Us
Run the experiment. Find out what really happens.
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