So what's fishy about the DNA?

The out-of-Africa theory has conceptual problems in evolution theory discussed in the previous article, in that Africa seems to be an unlikely location for the development of erectus subspecies. 

In this article we will discuss the vital genetic "proof" for Recent African Origins, which has always been suspect and is now regarded as partly discredited. The area is technical and of necessity so are our criticisms. However in the end they boil down to one thing  - the presumption that sapiens is a species is wrong, it is only a sub-species. So are the presumptions that Y-chromosome Adam and mitochondrial Eve were sapiens - Adam definitely was not and it is unlikely that Eve was. 

Our criticisms are the following

• genetic research been widely publicised earlier than was justified by the scientific validity of the results.The human geneticists have subsequently done nothing for their credibility by producing one "definitive" result after another which has been disproved within a couple of years.
• the number of SNPs used in construction of the cladogram was far too small. The attachment of more SNPs has removed much of the linearity from the Y-sequence - to the point that it no longer "proves" an African origin at all, and is mildly supportive of a South-east Asian origin. The method also ignored homoplasy (the possibility that two people with the same SNP value do not have a common ancestor with that value). 
• Only a very few individual sequences were used (Cann used 145 - see next section), missing the vast majority of the living relict "long thin lines" of DNA (and of course, the huge variety of extinct ones, including most of those found in ancient DNA).
• the method used for dating SNPs - using STR sequences - is notoriously inaccurate and tells us little about the earliest haplogroups (none of which appears to be single lineages) or their true age.

We believe that these problems can and will be fixed in the next few years.

Genetics and Out-of-Africa

The Recent African Origins theory received a massive underpinning  when in 1997 Rebecca Cann and colleagues produced after eight years' research into placental DNA a cladogram or table of mitochondrial descent for sapiens which "definitively proved an African mitochondrial Eve". [1] This was followed by the construction of a similar sequence from a Y-DNA "Adam" which appeared to clinch the argument. 

From that point on, the out-of-Africa theory was embraced with almost missionary zeal by human geneticists, and an army of laymen.  Assisted by the potent crypto-biblical imagery of Adam, Eve and the cladogram, various popular books such as Sykes brought the theory to wide public attention. From about the year 2000, genetic genealogy testing for the general public became available in most countries, and soon became an industry. The area became commonplace for  unsupported and often unlikely or even uneducated statements to capture media attention. The unfamiliar technical language of genetics and the cost of obtaining new (or existing) data made it difficult to examine the Recent Africa theory in detail for some time, although many palaeontologists remained sceptical.  

  

I am a mathematician who is interested in the subject of gross factual errors compounded by misuse of mathematics, and this has been one of the prime recent examples. It is almost laughable to imagine that a neat linear stepwise history of human development could be constructed against the background of the rich sweep of separate development, migrations and mixing even during recorded recent history, and which must have been occurring for millions of years.

However, the theory did provide a useful point of departure for a more accurate  picture which is now emerging. The public interest in the theory and in DNA testing for genealogy provided a large infusion of funds into palaeogenetic research which has allowed better methods to be developed and better data to be obtained.

To be fair, this is a new field generating cutting edge results and new techniques, and it is to be expected that early errors will be made which will be corrected as the field develops.

The Y-cladogram 

[1] I do not underrate the accomplishment of the Cann team nor their bravery in launching sucha revolutionary and unpopular theory - that we are all Africans. Cann received not only scientific criticisms, but also public and religious hostility with hate mails, crank mail, late night calls, and even a visit from the FBI.