The first humans evolved in Africa from a single female 100,000 years ago.
The Facts Are .....
There are numerous and diverse theories of human origin - not just an African one. There are two main groups providing hypothetical scenarios of human development based of the interpretation of existing data. The 'Out of Africa' camp are mostly geneticists who use data from mitochondrial DNA.
The second group, the 'Separate Evolution' camp, are mostly palaeoanthropologists who interpret fossil data. There is no 'absolute' theory of human evolution, as it depends on which data is being analysed, what the premises of the interpretation are, and the evolutionary framework with which the data is viewed. Creation Ex Nihilo, Vol. 13, No. 4, 1991 p:20-23
The theory that humans evolved in Africa more than 100,000 years ago, then migrated to Europe around 35,000 years ago is accepted by many evolutionary proponents as a fact. One part of the evidence for this theory is a small number of skeletal remains - their type and assessed age. Should older fossils be found elsewhere in the world, this theory will have to be terminated. Nature report in Sydney Morning Herald, 19/2/88
The origin of humans in Africa is also based on the fact that tools which were found there have been dated as 2.0-2.5 million years old. These are the 'oldest' human tools ever found. The fact that these are the oldest, doesn't necessarily make them the first. Science News, March 8, 1986 p:149
Another promulgated theory that modern humans evolved from an ‘African Eve' 300,000 years ago is actually based on unsubstantiated assumptions. The date was reached by calculating how long it has been since all mitochondrial DNA was supposedly the same, based on the hypothesis that this form of DNA mutates at a rate of 2-4% every million years. Such foundational speculation cannot produce truth. The Courier-mail (Brisbane), May 9, 1986 p:5; The Weekend Australian, March 8-9, 1986
'Evidence' from DNA in cell organs called mitochondria, has been used to support the theory that humans descended from an 'African Eve'. It has now been admitted that the computer program used in the analysis was flawed, being based on circular reasoning. Depending on the starting assumptions, any one of a billion family trees could be made just as plausible, with any possible area of the world as the centre of human origin. Science, Vol. 255, February 7, 1992 p:686; The Age (Melbourne), February 24, 1992
By studying mitochondria, Dr Rebecca Cann and Dr Mark Stoneking believe they have traced humans back to an origin in Africa 300,000 years ago. Douglas Wallace, studying mitochondria, has traced humans to Asia 100,000 years ago. The study of geological data has led Edmund Gill to trace human origins to Australia. The Courier-mail (Brisbane), May 9, 1986 p:5; The Courier-Mail (Brisbane), July 18, 1986; The Weekend Australian, March 3-4, 1986 p:17
"[Statements about human origins have] very little to do with the real data and a great deal to do with unstated assumptions ..... Much of what is said in other areas, I think, is also highly speculative".
A statement by Dr David Pilbeam, an expert palaeoanthropologist at the Boston Natural History Museum. From an interview with Luther Sunderland, and recorded in his book "Darwin's Enigma", Master Books: El Cajon (California), 1988 p:88-90