African Great Lakes

The African Great Lakes are a massive system of lakes located in the East African Rift.

This group of lakes holds a staggering amount of water. Together, they contain about 25% of the planet's unfrozen surface fresh water. This total volume is actually greater than the combined water of Lake Baikal and the North American Great Lakes. This region is vital for both nature and people. It supports incredible biodiversity and provides resources for many nations. The lakes are part of a larger geological feature known as the Great Rift Valley.

These lakes formed through complex geological processes. About 12 million years ago, the waters of the equatorial plateau flowed differently. They either moved west into the Congo River system or east toward the Indian Ocean. This changed when the Great Rift Valley began to form. A rift is a weak area in the Earth's crust. It occurs when two tectonic plates begin to separate. This separation is driven by currents in the Earth's mantle. As East Africa moved toward the northeast, it pulled away from the rest of the continent. This process often creates a graben, which is a trough or low area. Water eventually collects in these deep troughs to form lakes.

Not all lakes in this system formed the same way. Lake Victoria is a notable exception to the rift pattern. It is not actually located within a rift valley. Instead, it occupies a depression situated between the Eastern and Western Rifts. This depression was created by the uplift of the land on either side of it. Other lakes are categorized by where their water drains. Some lakes, like Lake Victoria and Lake Albert, drain into the White Nile. Others, such as Lake Tanganyika and Lake Kivu, drain into the Congo River. Lake Malawi drains into the Zambezi via the Shire River. Finally, some lakes have closed basins, meaning they do not drain into other rivers. Lake Turkana is a prime example of a closed basin.

Each lake in the system has unique characteristics. Lake Victoria is the world's second-largest freshwater lake by surface area. Lake Tanganyika is the world's second-largest freshwater lake by volume and depth. Lake Malawi is the eighth-largest freshwater lake by area. Lake Turkana is quite different from the others. It is the world's largest permanent desert lake. It is also the world's largest alkaline lake. The climate around Lake Turkana is hot and very dry. In contrast, the highlands of the region are relatively cool. These highlands experience abundant rainfall and have fertile volcanic soils.

The region has a deep history involving early humans. Around two to three million years ago, Lake Turkana was much larger and more fertile. This made the area a center for early hominids. Anthropologist Richard Leakey led many important excavations in this area. In 1972, researchers found Skull 1470, which was once thought to be Homo habilis. Some scientists now call it Homo rudolfensis. In 1984, the nearly complete skeleton of a Homo erectus boy, known as Turkana Boy, was discovered. Even older remains have been found, such as the 3,500,000-year-old Kenyanthropus platyops skull. This name means "flat-faced man of Kenya."

Nature thrives in these waters and the surrounding lands. The Western Rift Valley lakes are home to extraordinary endemic species. Endemic species are those found nowhere else on Earth. More than 1,500 species of cichlid fish live in these lakes. The region also supports 10% of the world's fish species. Large mammals like elephants, gorillas, and hippopotamuses inhabit the area. The East African rift system also acts as a flyway for migrating birds. In the shallows of Lake Turkana, you can see flamingos. These birds are supported by massive amounts of plankton in the water.

Today, the African Great Lakes region is home to many people and nations. Ten riparian countries border these waters: Burundi, the Democratic Republic of the Congo, Ethiopia, Kenya, Malawi, Mozambique, Rwanda, Tanzania, Uganda, and Zambia. In 2020, the population was estimated to be more than 50 million people. Swahili is the most common language spoken here. It is also an official language in five of these nations. Many people rely on fishing for their livelihoods. For example, Uganda is one of the largest producers of freshwater fish in the world. The region's economy is diverse, with varying growth rates across different countries.