The initial theory of continental drift was put forward by a German meteorologist Alfred Wegener in 1915. This theory did not seem credible until it was connected with the plate tectonic theory in the mid 1960's. The Tectonic plate theory had an advantage over previous predictions as it could be supported by observed occurrences. One such thing that supports these two theories is that seen from space the continents look as if they might once have been joined together.
This possible idea was then proved to be almost certainly true when fossils of similar plants, animals and similar rock types of a corresponding time period were found on the east coast of South America and the West coast of Africa.
This could be viewed by many as being an explanation but animals have been known to cross oceans and seeds of plants have also been known to travel great distances such as coconuts to other continents.
For example a bird might fly from one continent to another and settle in it's new home where it is subjected to the same climate, food and predators as it was subjected to at it's original home and so might evolve in the same way. Similar rock types can also be found throughout the world and so this is not conclusive evidence.
It could be proved in the future if measurements of the continents location were taken down over a long period to see whether they moved consistently in their predicted directions but this would be hard to prove as it would take hundreds of years to prove the continents truly were moving in consistent directions. It has though been measured that the continents do move a couple of centimetres each year and so far they have been moving in constant unchanging directions thus...