As you look at Figure 8.4.4, the most obvious physical characteristic is the continents themselves. The physical isolation of North and South America, Australia, and Africa served as a barrier against migration to and from those areas during much of human history. It is only during the last millennium, when seafaring vehicles were more fully developed, that we began to see widespread migration from one continent to another. Consequently, the development of those areas has been greatly influenced by countries that had exploring and colonizing policies.

When you learned the names and locations of the continents, you learned that Europe and Asia are labeled as two separate continents. This may seem confusing to you; it is to me! As you can see by looking at the map, the continents of Europe and Asia are really one big landmass. The separation of the two continents is really a cultural separation caused by a natural feature of the earth.