No boats required. In the distant future, most if not all of today's continents (brown fragments, depicted with current-day outlines) will assemble into a single landmass called Amasia (shown approximately 100 million years from now). Over the next few hundred million years, the Arctic Ocean and the Caribbean Sea will disappear, and Asia will crash into the Americas forming a supercontinent that will stretch across much of the Northern Hemisphere. That's the conclusion of a new analysis of the movements of these giant landmasses. Unlike in today's world, where a variety of tectonic plates move across Earth's surface carrying the...