The Theory of Continental Drift
The Theory of Continental Drift was proposed by Alfred Wegener in the early 1900s, who noticed that the coastlines of South America and Africa fit like puzzle pieces and hypothesized that continents were once joined in a single landmass that drifted apart. In Amplify Science (California) Grade 7, Chapter 3: Investigating the Rate of Plate Movement, students learn how Wegener's radical idea laid the foundation for plate tectonics.
Key Concepts
In the early 1900s, a German scientist named Alfred Wegener challenged the idea that continents were fixed. He noticed that the coastlines of South America and Africa looked like fitting puzzle pieces and proposed the theory of continental drift .
Wegener hypothesized that the continents were once joined in a single landmass and had drifted apart. Although he lacked a mechanism (he didn't know about plates yet), his radical idea laid the foundation for modern plate tectonics.
Common Questions
What is the theory of continental drift?
Continental drift is Alfred Wegener's theory that the continents were once joined in a single supercontinent (Pangea) and have slowly drifted apart over millions of years.
Who proposed continental drift and what was his evidence?
Alfred Wegener proposed continental drift in the early 1900s. His evidence included the matching shapes of South American and African coastlines, identical fossils on separated continents, and similar rock formations.
Why was Wegener's theory initially rejected?
Wegener's theory was initially rejected because he could not explain the mechanism—what force was moving the continents. The mechanism (mantle convection and plate tectonics) was discovered decades later.
Where is the Theory of Continental Drift covered in Amplify Science Grade 7?
Continental drift is covered in Amplify Science (California) Grade 7, Chapter 3: Investigating the Rate of Plate Movement.