During Alfred Wegener's time (early 20th century), the concept of earth's crust being made of plates that move was still unknown to scientists. Wegener proposed the theory of continental drift in 1912, suggesting that continents were once part of a single landmass and have since drifted apart. However, the mechanism behind this movement—specifically the idea of tectonic plates and plate tectonics—was not developed until the mid-20th century, long after Wegener's time. The other points you mentioned, such as fossils found in various places, the alignment of mountain ranges, and the fitting together of continental coasts, were observed and noted but did not provide a complete explanation for why these phenomena occurred.
What was unknown to scientists
during Wegener’s time?
Fossils were found in many
places.
Mountain ranges of some
continents lined up.
The coasts of some
continents fit together.
Earth’s crust is made of plates
that move.
1 answer