Out of Africa (DLC – Ascent of Man)
“Man is unique not because he does science, and he is unique not because he does art, but because science and art equally are expressions of his marvellous plasticity of mind.” – Jacob Bronowski
Long, long ago, man (Homo Sapiens) walked out of Africa into the middle east on a journey that would eventually take them to the moon. However, this ‘voyage’ is not as straight forward as the anthropologists and archaeologist would have you believe. For on this incredible journey, not all of mankind would walk the same path to the industrialisation and technology that we would consider as natural evolution today. On this journey to mankind’s destiny, there were casualties within societies that fell behind, as they failed to adapt to the rigours of the changes that created our modern society.
Originally, anthropologists had believed that our ancestral journey started 100,000 years ago, when Homo Sapiens (Mankind) ventured ‘Out of Africa’ to inhabit eventually the entire earth’s surface through ‘natural migration’. The dates of these migrations have altered drastically in recent years with the introduction of ‘archaeogenetics’. This science was introduced in the 1990s and allowed us to look deep into our own DNA to find genealogical connections and linkages, which can be joined together with Palaeolithic archaeological findings that indicate that this single migration theory is now incorrect or misunderstood.
We currently believe that there were as many as three migrations of ‘Humanoids’ – from the ‘Homo’ family, who left Africa, which is commonly termed as the ‘cradle of humanity’. The first migration was about 1.75 million years ago, when Homo Erectus left East Africa, then spread wide for over a million years, and found as far away as China and South America. Homo Erectus was primitive in many aspects compared to the later migration species such as Homo Sapiens, but it represented a benchmark of change to a recognisable humanoid from his great ape origins. Erectus brain size was much larger, with a face including projecting nasal bones, small teeth, a human-like posture for the skull and a body frame of human proportions. Erectus disappeared at the time of second migration, whether this disappearance is a connection or a coincidence is unclear at present (as the fossil record is scant), but as we will see, this may not be the only time that a humanoid species disappears quite mysteriously after an African migration.
The Second migration happened at a somewhat closer date of around 500,000 years ago, when Homo Neanderthal left Africa and moved north into Western Asia. Neanderthals had an elongated superior pubic and rounder femora and ramus bones (in the Pelvic region) like Erectus. A larger brain volume like ours; a high and arched temporal bone (in the skull); reduced interorbital breadth (distance between the eyes); reduced total facial projection (front profile); a lightly built tympanic (middle ear bone) and in many Neanderthals, simplification and shrinkage of tooth crowns like ourselves and weak or absent iliac pillar (in the hip).
There were more distinctive features than Erectus such as body shape, rib cage and limb proportions, but the clearest difference was in the skull; double-arched but small occipital torus with centre pit (the suprainiac fossa at the back of the skull); a spherical vault shape in rear view; distinctive shape of the semi-circular canals of the inner ear; strong mid-facial projection and cheekbones that are inflated and retreat at the sides; a high, wide and projecting nose, large and near circular orbits; a high but relatively narrow face and enlarged front teeth (incisors), which are hollow in the inside surfaces of the upper centrals, but most distinctive than all was the strong brow ridge.
Neanderthals were separated as a species for 700,000 years from Sapiens and a million years from Erectus. Similarly, Coyotes and Wolves have been isolated for about 1 million years and far more generations. Interestingly, they can still produce fertile offspring by ‘interbreeding’; similar findings existed between lions and tigers that can interbreed even after 5 million years of separation. These examples clearly show that Sapiens and Neanderthals and even Erectus were capable of interbreeding when given the right circumstances.
The reason I have mentioned interbreeding is because any discussion of our evolution has to explain how these humanoid cousins come into being. Most people have heard of Darwin and his famous book ‘On the Origins of Species’ – but few have gone on to understand what he was trying to tell us within this famous book. Most online encyclopaedias will tell you that: “Darwin’s book introduced the scientific theory that populations evolve over the course of generations through a process of natural selection. It presented a body of evidence that the diversity of life arose by common descent through a branching pattern of evolution. Darwin included evidence that he had gathered on the Beagle expedition in the 1830s and his subsequent findings from research, correspondence, and experimentation.” All very nice but missing the main point of Evolution.
So what is ‘natural selection’ or as some put it ‘survival of the fittest’?
Quite simply it’s the ‘mutation’ of the species. The classic case is the neck of a giraffe, which started history as being no bigger than a horse’s neck. The giraffe’s neck does not get longer over time; it’s fixed in length, but an off-spring that has genetically mutated may have a neck an inch or two longer than one of their siblings. This sibling will therefore be able to feed more successfully as they will have access to the higher food sources – and this is what is meant by the term ‘survival of the fittest’. Consequently, when this sibling mates the genetic probability is that at least one if not more of its children will have the same neck size and so through inbreeding (with giraffes with this larger neck size over the
course of time) the longer necked giraffe will now become the norm for this genetic branch of the giraffe’s family tree and will be better adapted to surviving in times of shortage. This mutational process continues for many hundreds of generations until the giraffe’s neck is the size we see today.
It is thought that six million years ago this kind of mutation created the first humanoid (Homo) as a branch of the primate tree. Moreover, what we need to understand is that this mutation of the species is ‘ongoing’ and from this humanoid genetic tree created Homo Erectus, Homo Neanderthal and us Homo Sapiens. Even so, this is not an exclusive club as there will be many ‘sub-species’ of humanoids as these cousins can effectively interbred with each other producing other kinds of humanoids, which are currently being found in the fossil records, confusing Anthropologists because of their diversity.
When Sapiens left Africa, they had two distinctive routes they could have taken. The best and fastest route would have been over the Red Sea to the Middle East, yet the archaeological evidence shows that they took the ‘foot route’ instead through present Egypt into Palestine. This was the same route taken by the two former Homo migrations by Erectus and Neanderthal, as both species have now been found in this area through archaeological record, which leads us to conclude that these first two humanoids species were unwilling or unable to swim and so were completely land based.
It is an interesting and relevant fact that most native Africans are poor swimmers, which is surprising for people who are surrounded by lakes and rivers. A little-known fact is that non-Africans have an extra layer of fat in their skin, known as ‘subcutaneous tissue’, as do most aquatic mammals – this difference in the body type can best be seen in the death rates from drowning, where African people are twice as likely to drown than white people, even in swimming modern pools.
Where did Homo Sapiens get the ability to swim and use boats in our evolutionary history?