Lake Malawi is an African rift lake, formed as the earth’s crust is slowly spreading apart. This lake is one of the deepest in the world and one of the lead geologists, Dr. Andy Cohen of the University of Arizona (go Cats!) says that the lake "acts like a rain gauge" and through their drilling expedition they have determined that the lake at one time dropped nearly 2,000 ft between 135,000 and 90,000 years ago. This drought in what is now a lush tropical part of Africa may explain why Man’s early ancestors migrated from that continent. More after the break.