The theory of Pangea was first proposed by Alfred Wegener in 1912. Wegener was a German meteorologist and geophysicist who noticed that the continents of Africa and South America seemed to fit together like pieces of a puzzle. He also found evidence of similar fossils and rock formations on different continents, which suggested that they had once been connected.

Wegener's theory was not widely accepted at first, because there was no clear explanation for how the continents could have moved. However, in the 1960s, the theory of plate tectonics was developed. Plate tectonics is the theory that the Earth's crust is made up of large plates that move slowly over the Earth's surface. This theory provided an explanation for how the continents could have moved, and it led to the widespread acceptance of Wegener's theory of Pangea.

Here are some of the evidence that scientists used to support the theory of Pangea:

1. Similar fossils on different continents

2. Similar rock formations on different continents

3. The shape of the continents

4. The distribution of coal deposits

5. The distribution of mountain ranges

The theory of Pangea is now well-established, and it is considered to be one of the most important theories in geology.