Why are there warm plant fossils from a tropical climate being found in Antarctica? Continental Drift can help explain why. Continental Drift states that the continents and the plates their on drift on top of the mantle, a layer of molten rock under the Earth's surface. Pangaea was a super-continent of all the continent today put together. It split apart to form our current continents that will, in millions of years, have moved again. This also helps the theory of the plants being found in Antarctica.
To state this theory, Antarctica had must have been warm at some point, right? Scientists believe that Antarctica was actually in a warmer climate until Pangaea broke apart. Since the continents moved, climates changed as well. Antarctica floated to a colder area and, with the icy cold water surrounding it, slowly grew to be an icy place.