Continental Drift and Plate Tectonics

Continental drift was an early theory explaining how continents moved, largely associated with Alfred Wegener.
Wegener proposed that all continents were once part of a singular landmass known as Pangaea.
He published his theory in the early 20th century based on evidence from biology, botany, and geology.

Fossils of the mesosaurus, a freshwater reptile, are found exclusively in southern Africa and South America, indicating a shared habitat.
Plant fossils discovered in Svalbard, Norway, are of tropical species, suggesting it had a warm climate in the past.
The fit of the east coast of South America with the west coast of Africa resembles a jigsaw puzzle, showing geological similarities.
Appalachian Mountains in the eastern USA share geological traits with the Caledonian Mountains in Scotland.

Pangaea existed approximately 240 million years ago and started breaking apart around 200 million years ago.
Several supercontinents have formed and fragmented during Earth's history, including Pannotia (600 million years ago) and Rodinia (over 1 billion years ago).

Wegener's theory lacked a mechanism to explain continental movement, leading to skepticism among scientists.
Current understanding attributes continental movement to tectonic plates, massive rock slabs that constantly shift and interact.

Seafloor spreading occurs at mid-ocean ridges, where molten rock adds new oceanic crust, pushing continents apart.
The North American and Eurasian plates are drifting apart at about 2.5 centimeters (1 inch) per year due to the Mid-Atlantic Ridge.
Rift valleys form when a landmass is splitting apart, such as the East African Rift, which will eventually separate Africa into two continents.