Great Lakes form a single, naturally interconnected body of fresh water, within the Great Lakes Basin. They form a chain connecting the east-central interior of North America to the Atlantic Ocean. From the interior to the outlet at the Saint Lawrence River, water flows from Superior to Huron and Michigan, southward to Erie, and finally northward to Lake Ontario. The lakes drain a large watershed via many rivers, and are studded with approximately 35,000 islands. There are also several thousand smaller lakes, often called "inland lakes," within the basin. The surface area of the five primary lakes combined is roughly equal to
African Great Lakes "Homo erectus" boy was discovered. More recently, a 3,500,000-year-old skull was discovered there, named "Kenyanthropus platyops", which means "The Flat-Faced Man of Kenya". Fishing—primarily of tilapia species but also of Nile perch—provides the main livelihood. With four Great Lakes on its borders, Uganda ranks as one of the world's largest producers of freshwater fish. The climate and rich volcanic soils in the highlands also sustain intensely cultivated croplands. The economies of the Great Lakes region states have different structures and are at various stages of development. The GDP real growth rate ranges from 5.1 percent in Burundi to 6.4 in