It was known that lands now far apart and with very different climates contained the same kinds of fossil plants and animals. For example, certain dinosaur fossils have been found across central South America and western central Africa, and nowhere else. Identical fossil plants have been found in southern South America, southern Africa, India, Antarctica, and Australia. Evidence of an ancient glacier that was once one large ice cap can be found in South America, Africa, India, and Australia. These areas would join if the present continents were moved so that they fitted together into one whole.

More than 225 million years ago all of Earth's continents formed one large land mass scientists call Pangaea. Over millions of years, Pangaea broke up into a northern section called Laurasia and a southern section called Gondwanaland. These, in turn, became the continents we know today.

This illustration shows the location where fossils remains of plants and animals have been found on the modern day continents that were part of Gondwanaland about 290 to 225 million years ago. The Continents are (from left) South America, Africa, India, Antarctica (white), and Australia. Over millions of years, as these continents moved into their current positions, India moved northward until it met and joined the continent of Asia.