Plate Tectonics

Plate Tectonics

Online interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about interpreting evidence that scientists use to explain the theory of continental drift.

Continental drift theory states that the continents were once one landmass that broke apart and drifted to the present positions.

These tasks are about the evidence that scientists use to support their theory that Africa and South America were once joined.

continental drift showing map of world during jurassic period  continental drift showing map of world present day

continental drift animation

Question 1Change answer

 

The diagram above represents scientists' ideas about how they think Africa and South America were once joined. One type of evidence the scientists used to build this theory is fossil evidence.

Task One

What idea about fossil remains does this diagram show?

Question

Scientists believe that reptiles originated in one place and spread across the continents when the continents  were joined together. 

Task Two
Could the reptile Cynognathus have travelled between these continents if they were not joined?

 

    • Yes

    • No

Explain why

Question

Task Three
Could the reptile Mesosaurus have travelled
between these continents if they were not joined?

 

    • Yes

    • No

Explain why.

Question 1Change answer

Task Four

From the diagram below, what evidence other than fossil evidence might the scientists have used to support their theory that Africa and South America were once joined?

Task administration: 

Tasks are online. Students can work independently or discuss their choices in pairs or in groups. 

Copyright: 
Graphics: Public domain, Wikipedia.
Level:
5
Curriculum info: 
Science, Understanding about science, Planet Earth
Keywords: 
plate tectonics, continental drift, fossils
Description of task: 
Students answer two multichoice questions giving explanations for their choice and two short answer questions.
Curriculum Links: 
Science capabilities
The capabilities focus is brought about by the conversations you have and the questions you ask 
Capability: Interpret representations
Scientists represent their ideas in a variety of ways, including models, graphs, charts, diagrams and written texts. This resource provides opportunities to discuss how scientists represent ideas about fossils and continental drift in diagrams. 
Science capabilities: 
Interpret representations
Answers/responses: 

Q1. The fossil remains of Cynognathus and Mesosaurus are found across the continents of Africa and South America.

Q2. No.  Cynognathus is a land reptile and would not have been able to swim the large distance that separates the continents of Africa and South America as they are today.

Q3. No.  Mesosaurus is a freshwater reptile and would not have been able to survive in the salt water that separates the continents of Africa and South America.

Q4. The shapes of the continents show that they could fit together.

Teaching and learning: 

Reading diagrams is an aspect of communicating in science. In the continental drift diagrams students need to know that the visual cues mean that:

  • the picture of each animal represents many millions of fossils of that species;
  • the coloured bands represent the fossils being found across the whole of each continent [not just in the banded area];
  • the size of the picture of each animal represents the focus of the diagram [many other fossils of different species are found in these continents but just these two are focussed on here];
  • the size of the animals and the continents are not to scale.
Diagnostic and formative information: 

All the students in the online trial recognised that the pictures and graphics used in the diagram represented fossil remains found in both continents. However one misconception was that the fossil remains were found only in the coloured areas rather than across the whole landmass.

Most students recognised that Cynognathus was a land mammal and could not swim. Some students thought that if the mammal could swim it could easily swim between the continents. The perception of distance between the continents was a misconception for these students. 

A few students said that Mesosaurus would also easily swim from one continent to the other. These students had not read that Mesosaurus is a freshwater reptile and they also held a misconception about the distance involved between the continents. 

Most students said that the continents shape showed they had once fitted together as one landmass.

Next steps: 

Students who found it difficult to understand the continental drift diagrams could pracitise reading and interpreting other science diagrams such as: water cycle diagrams; carbon cycle diagrams; food webs etc. Students could take note of:

  • What the representation tells us about science knowledge; and
  • What type of communication conventions are being used.

In two of the questions students perceived the distance between the continents as easily swimmable for Cynognathus and Mesosaurus. These students could practise looking at scale by examining: maps of distances between towns; between cities; between countries; between planets of the solar system; and/or any other visual or conceptual models that could help them make scale much more understandable.