If we could visit our planet 250 million years from now, we would hardly recognize it. On the one hand, the emerged lands have been reunited in a single supercontinent, known as Pangea Ultima. Much of it is inhospitable desert, and the shores are battered by fierce storms.
The all-encompassing ocean appears turbulent, but it is stagnant at the bottom, and oxygen and nutrients are in short supply. Such a supercontinent, conceived by geologist Christopher R. Scotese of the University of Texas, is not the first to have existed.
Nor will it be the last. Scientists suspect that the movements of the continents are cyclical – they move about 15 mm a year – and that every 500 million years they cluster together. Now, we are in the middle of a cycle. With a period three times longer than the time it takes for our solar system to circle the center of the galaxy, it is one of the greatest patterns in nature.
