Scientists believe the lineage of cichlid fishes (Family Cichlidae) that now inhabit the rivers of the Congo, Zambezi, Okavango, and Limpopo Rivers can all be traced back to a single, 'lost' lake in Botswana.

This ancient lake, referred to as Lake Makgadikgadi, is believed to have dried up over 2000 years ago. Current genetic research suggests that Lake Makgadikgadi could have been an evolutionary 'hotspot' for cichlid species.

Find out more: Lost African lake spawned fish diversity beyond belief (National Geographic)