File:Lake Tanganyika and Lake Rukwa (MODIS).jpg

English: Separated by only 60 miles (100 km) of rugged East African Rift country, Lake Tanganyika and Lake Rukwa offer stark contrasts in appearance and biodiversity.

Lake Tanganyika, located on the left (west), is the Earth’s second deepest lake and also the longest freshwater lake, stretching for more than 400 miles (644 km) across four countries (Tanzania, Democratic Republic of the Congo, Burundi, Zambia). Plunging to a depth of 4,820 feet (1,470 meters), Tanganyika provides a home to about 1,500 species, including a vast array of spectacular fish known as cichlids, many of which have developed unique behaviors as they evolved in various niche habitats of the lake. Roughly half of all the species of Lake Tanganyika are endemics, existing nowhere else in the world.

Lake Rukwa is much smaller and shallower, and the water is alkaline rather than fresh. With an average depth of only 10 feet (3 meters) and a maximum depth of 49 feet (15 meters), the water levels fluctuate with the rainfall and inflow of rivers, often looking murky and muddy. In the dry season, the lake can even separate into two basins. Lake Rukwa, which sits in both Tanzania and Zambia, has much less biodiversity than Tanganyika. Although total species are few, it does host some endemic cichlids and catfish, as well as the largest population of crocodiles in Tanzania.