The Southern Dispersal Route refers to a theory that an early migration of modern human beings left Africa as least as long ago as 70,000 years and followed the coastlines of Africa, Arabia and India, arriving in Australia and Melanesia at least as early as 45,000 years ago. It is one of what appears to now have been multiple migration paths that our ancestors took out of Africa.
Most versions of the southern dispersal hypothesis suggests that modern H. sapiens with a generalized subsistence strategy based on hunting and gathering coastal resources (shellfish, fish, sea lions and rodents, as well as bovids and antelope), left Africa between 130,000 and 70,000 years ago [MIS 5], and traveled along the coasts of Arabia, India, and Indochina, arriving in Australia by 40-50,000 years ago.
By the way, the notion that humans frequently used coastal areas as pathways of migration was developed by Carl Sauer in the 1960s. Coastal movement is part of other migration theories including the original out of Africa and the Pacific coastal migration colonizing the Americas ca 15,000 years ago.
Southern Dispersal Route: Evidence
Archaeological and fossil evidence supporting the Southern Dispersal Route includes similarities in stone tools and symbolic behaviors at several archaeological sites throughout the world.
- South Africa: Howiesons Poort/Stillbay sites such as Blombos Cave, Klasies River Caves
- Tanzania: Mumba Rockshelter
- Kenya: Enkapune Ya Muto
- United Arab Emirates: Jebel Faya
- India: Jwalapuram and Patne
- Sri Lanka: Batadomba-lena
- Borneo: Niah Cave
- Australia: Lake Mungo and Devil's Lair
Chronology of the Southern Dispersal
The site of Jwalapuram in India is key to dating the southern dispersal hypothesis. This site has stone tools which are similar to Middle Stone Age African assemblages, and they occur both before and after the eruption of the Toba volcano in Sumatra, which has recently been securely dated to 74,000 years ago. The power of the massive volcanic eruption was largely considered to have created a wide swath of ecological disaster, but because of the findings at Jwalapuram, that has recently come into debate.
Further, the presence of other humans sharing planet earth at the same time as the migrations out of Africa (Neanderthals, Homo erectus, Denisovans, Flores, Homo heidelbergensis), and the amount of interaction Homo sapiens had with them during their sojourns is still widely debated.
Other parts of the southern dispersal route theory not described here are genetic studies examining relict DNA in modern and ancient humans (Fernandes et al, Ghirotto et al, Mellars et al); comparisons of artifact types and styles for the various sites (Armitage et al, Boivin et al, Petraglia et al); presence of symbolic behaviors seen at those sites (Balme et al) and studies of the environments of the coastal routes at the time of the expansion outward (Field et al, Dennell and Petraglia). See the bibliography for those discussions.