To understand the life of this future world, we need to understand the shape of this future world. In the 1870s, geographer Alfred Wegener discovered that many of the Earth's continents fit almost perfectly with each other. He also saw that many of the world's oldest mountain ranges fit very well with each other as well, as if they were once connected together. Not only that, but fossils from ancient animals seemed to suggest that animals were crossing between the continents, even though they were separated by thousands of miles of ocean. Wegener came up with a theory that at one point in the Earth's past, all the continents were once connected in one giant continent called “Pangea” with a global ocean covering over half the globe. Many scientists criticized Wegener, as he had no way of knowing how continents could move.
However, in the 1960s, it was discovered that the Earth's crust was not one solid piece, but rather a large collection of plates floating on the Earth's mantle. These plates crash and bump into each other to create mountains or dive under each other to create trenches. These plates move slowly, only a few centimeters every year, about as much as human fingernails grow.
Computer modeling and geologic evidence have come up with something called the “Supercontinent Cycle” or the “Wilson Cycle”. It shows that over a period of 300-500 million years, the continents break apart and then recombine in a massive supercontinent that lasts at least 100 million years before breaking apart. Over the past 3.6 billion years, there have been roughly 12 supercontinents that have formed and they have had quite a large impact on the climate of the Earth and this will continue into the future.
At present, the Atlantic Ocean is getting wider and the Pacific Ocean is getting smaller due to oceanic trenches. How these oceans evolve will determine the future of the planet. By 50 Million Years from now, the Mediterranean Sea will have closed and formed into a new mountain range. Australia will have drifted northward and collided with Indonesia. Antarctica will have drifted northward and melted, which, along with Greenland's ice cap, will raise sea levels by >70 meters. All low lying coastal regions will flood. It will be the end of geography as we know it. After 50 Million years, things start to get speculative. There are roughly four possible supercontinents arrangements, Pangea Proxima, Novopangea, Amasia, and Aurica.

In the Pangea Proxima model, subduction zones will form along the Atlantic Ocean and eventually cause the Atlantic to close, as well as the Indian Ocean. By 100 Million years from now, the Atlantic will begin to close and the Americas will begin migrating back to Africa. By 200 Million years from now, North America will merge with South America and collide with Africa. The southern tip of South America will collide with Indonesia. Australia will begin to collide with Antarctica. By 250 Million years from now, there will be two continents, one comprising Africa, Europe, Indonesia, North and South America located where the Atlantic once was, with the Indian Ocean becoming an inland sea. A second continent comprising Antarctica and Australia will migrate back to the South Pole, building a new ice cap.

---

This is only one of four possible supercontinents. This is Pangea Proxima, the most likely continent, but the continents could assemble in any way over 100 million years from now.