Image courtesy of NASA.
Anyone with a map can see that Asia and Europe are connected. They are often called Eurasia for that reason. The divide is pretty arbitrary, more culturally than scientifically defined. So, is it fair to say that there are actually only six continents? It turns out that this is just the first slippery step on a well-oiled slope. What about North America and Asia? They are connected by the Bering Sea Shelf, once dry land crossed by humans and flooded only in the geologically recent past. Technically speaking, that makes Asia, North America and Europe all one continent. Does that mean there are only five? This is an incredibly complex question that geologists are grappling with. Read on in The New York Times article that I wrote on this here.