Out of Africa thesis for modern Man growing ever more dubious

Robert Henderson

A 400,000 year old  fossil shell with geometric-style  marks thought to have been deliberately made  on it by Homo erectus  has been discovered in  in Java.  If this is true, and the marks do indeed look  deliberate,  then it is strong pointer to a form of Homo  considered  decidedly primitive compared with modern Man  having an ability to think abstractly and to translate that thought into physical representation. The discovery is impressive because it pushes  back the possession of such an ability hugely beyond  the advent of  Homo sapiens  150,000-200,00 years ago.

If this is a correct interpretation of  the marks on the shell it has a profound  implication: the closer the shape of intelligence in older forms of Homo to those of younger  forms,  the stronger the likelihood of interbreeding because general behaviour  in  the older and younger forms would have had considerable similarities.

This is important both in itself and because it undermines the Out of Africa theory, which has been in the ascendency arguably since Darwin fingered Africa as the birthplace of Homo.   The latter reason has great political resonance in the West because it can be fitted neatly into the predominant liberal internationalist credo of the First World. It allows the liberal internationalist to place their claim that humanity is just one big family  without any meaningful difference on the supposed rock of a common ancestry. Even better for the liberal, the common ancestor happens to be found in the part of the world whose populations are  of particular interest to  the white liberal, namely, those of  black Africa.

When interbreeding of different species of Homo is introduced into the picture it shows  human populations living today  as being more genetically  diverse than the Out of Africa theory allows and removes the claim, overt or by implication, that ultimately all human behaviour  and achievement derives from  the descendants of Africans.  Most devastatingly for the liberal  it raises  the possibility  that the  widely differing cultures humans have created  are at least in part,   a consequence of   genetic differences between varieties of Homo.  Moreover, because Man is differentiated profoundly by culture, the widely accepted definition  of a species – a population of freely interbreeding organisms sharing a common gene pool –   is  unsatisfactory,  for  clearly Man is  more  than  an  animal  responding   to   simple  biological   triggers.  When   behavioural differences  are perceived as belonging to a particular group  by  that group  as differentiating  members of the group from other  men,    they perform the same role as  organic differences for  they divide Man  into cultural species.

It is true that so far the amount of genetic difference attributed to interbreeding is small, perhaps 1-3% of Neanderthal genes in  modern Man outside of Africa .  There are two points to bear in mind. First, a small difference in genetic profile could have a profound effect on ability and behaviour.  The most crippling and dangerous diseases can be the result of a single gene differing from the norm.

If it is accepted that genes have  a fundamental role in shaping behaviour and  general personality, then differences in genetic makeup, even if they only affect a small number of genes,  could be marked.  Do genes have such as  role? It is difficult to see how they could not,  because  to maintain that they do not  would in effect be to argue  that all parts of the body are subject to genetic control but those responsible for the functioning of the mind.  There is also the evidence from animal breeding  that  behavioural and temperamental traits can be successfully enhanced  through selection directed by humans, dogs being the prime example.  It would be very odd if the human template was so  completely different from that of  animals  that  in this one respect it was utterly  different.

But interbreeding could also  create important external physical changes which had the potential to alter behaviour both of those who acquired the changes and those  who did not. For example, analysis of Neanderthal DNA suggests that breeding between  Neanderthals and Homo sapiens in Europe and Asia  was at least partially responsible for modern  Europeans and Asians  having  lighter skins and possibly straight  hair.

The second consideration is that humans have been distinctly rare for most of human history.  Estimates are obviously very  difficult to  make for the distant past but, for example, the US census department gives an estimate of between 1-10 million for 10,000 BC.    A small population would be more susceptible to both a valuable mutation spreading  rapidly through it and to maintaining the mutation.  That would enhance diversity  within  a sizeable population in a specific area such as Europe..

The evidence for interbreeding  between different varieties of Homo  has been growing in recent years through the  vast technological improvements in DNA retrieval and reading.  From this comes  objective evidence that modern Man outside of Africa has Neanderthal ancestry.  The gene sequencing of a third species or subspecies of Homo, the Siberian Denisovans also shows evidence crossbreeding with Asians.  There is also a another  candidate for interbreeding  as  yet  unnamed.

This may just be the tip the  interbreeding  story because discovered  human fossils , though  much more plentiful now than they were even fifty years ago, are still very meagre.  Fossils are placed in  general type classifications such as  homo erectus and Homo habilis which may have substantial differences in form or are classified as this or that from very incomplete fossils.  Interbreeding could have been much more varied  than the present evidence shows.   If  so,  the amount of genetic mixing could be far greater than is presently imagined, because  it would not simply be a case of two distinct species or varieties of Homo mating,  but the descendants of  differing varieties of Homo who have mated then  mating with other hybrids whose hybridity is  of a different type.  For example, suppose there were four different types of Homo in the same geographical  area. Types 1 and 2 mate. Their children are hybrids. Types 3 and 4 mate. Their children are hybrids. The children of 1 and 2 then mate with the children of  3 and 4 producing further hybrids.  Of course, this type of interbreeding would apply to sub-Saharan Africa as well as the rest of the world, so that any emigrants from Africa into Eurasia would almost certainly be carrying a mixture of genes from various forms of Homo.

Another  interesting  trait  is that  members of a  species  will  have different  breeding  propensities  across its  distribution,  that  is, members of the supposedly single species will breed differentially with different parts of the total species population.  For example,  take an animal  which is common to Europe and bring individuals from  different geographical parts of the continent together and it may be that those found in the  East of  the distribution  will be less likely or refuse altogether to  mate with the those in the West.  These barriers to breeding are clearly not purely due to major differences in physical biology. Probably there is a strong component of behavioural difference which reduces the propensity to breed.

It  is worth adding that the traditional concept of a species is far from secure. It is a man-made classification which is often found wanting. For example,  the North American Ruddy Duck and the  European  White-Headed Duck are classified as separate species.  The introduction of the Ruddy Duck  to  Europe has resulted in widespread interbreeding  between  the supposedly  separate  species to the extent that  conservationists  now fear for the survival of the White Headed Duck.  It is also true that a growing  amount  of   traditional  taxonomic  classification  is  being overturned by DNA analysis.

There is nothing surprising about varieties of  Homo interbreeding.   Many animals of  closely related species could produce offspring if they were willing to mate as can be seen from the successful human instigated  inter-breeding  by artificial insemination of, for example, lions and tigers and inter-species mating in the wild.  The offspring  of such intra-species breeding , whether artificial or in the wild,  are  often sterile, but not invariably.

Animals use various triggers to breed: aural, chemical, condition of feathers  and so on. These are seemingly automatic processes whereby one individual responds to another without conscious thought. Even behavioural triggers such as mating rituals can be viewed in the same light, although in such cases the process of acceptance and rejection may include an element of  higher understanding  as such a ritual is often complex and it is not easy to see exactly how it could be a simple programmed response.

Man, although not divorced entirely from  such triggers, adds conscious thought to the process of mate selection. Does that  put Man in an entirely separate category to all other organisms, namely,  the one organism who can potentially breed freely across the entire species population?  Potentially yes but in practice no,  for Man’s capacity for conscious thought and decision making does not mean  his breeding is not constrained by the triggers which control other organisms, especially behavioural. For example, most people choose mates who are of the same race as themselves even when they have ample opportunity  to do otherwise.

Nonetheless,  any organism with a degree of self-consciousness and,  perhaps even more importantly,  language  could and almost certainly would go far beyond  the triggers to separation of animal species which  have neither significant consciousness nor,  most importantly, language.   The possession of language in particular would provide a means to overcome any reluctance to breed with those of a different variety of Homo, for it would not only allow a means to share and discuss ideas with their own tribe or band, but also to communicate with mates  of a different  variety.

Even if some or much of the interbreeding took place by force,  language would still be a facilitator because it would make the females seem to be similar to females from their own tribe.  There may even have been the practice of swapping females between tribes or bands of different varieties of human, a practice evident  amongst tribal peoples even today.

The cranial capacity of extinct t varieties of Homo is often used as the starting point for assessing their mental capacity. But size of brain is not everything. Oliver Cromwell had a cranial capacity of 2,000 cc; the novelist  Anatole France one of less than 1,000 cc.   Neanderthals had an average brain size larger than that of modern  humans.   The shape of a brain with differing emphases on its various functions is also taken as a pointer to mental capacity,  for example, Neanderthals  are routinely   said to have  more of the brain devoted to sight and body control, which  implies less  capacity for social interaction skills and abstract thought.  However,  this  supposed difference from Homo sapiens is still a matter of debate amongst academics and there is growing evidence  of Neanderthal cultural sophistication.  Indeed, research published in early 2014 concluded:

Modern humans are usually seen as superior in a wide range of domains, including weaponry and subsistence strategies, which would have led to the demise of Neanderthals.”

“We have found no data in support of the supposed technological, social and cognitive inferiority of Neanderthals compared to their contemporaries…their demise was clearly more complex than many archaeology-based scenarios of ‘cognitive inferiority’.”

If the mental capacity  and behavioural sophistication of older forms of Homo was much greater  than  has  often been conjectured,  the willingness and ability to mate  with them by more advanced forms would have been more frequent.  The evidence of the fossil  shell  mentioned at the beginning  points to behaviour which we would consider very human a very long time ago.  Another impressive  ancient example of ability in older forms of Homo has recently been found  at a 350,000 year-old  site in Israel  where there is evidence  of regular and controlled use of fire.   It may be that the likes of Homo erectus and  Homo habilis were far more like Homo sapiens than they are given credit for and  later forms ever more so the nearer they come to the present.

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