A recent after-dinner discussion led to us speculating as to how humans and our world would change in, say, 100, 1,000 or 10,000 years. One approach was to look back 100, 1,000 and 10,000 years and forecast changes in the future to be at the same rate as in the past. But this is easier said than done. Extrapolation along a specified path of change is only a matter of elapsed time but when the direction itself changes, extrapolation does not work. Furthermore, any extrapolation is hampered by the fact that the rate of change is itself changing. However, there are some aspects of human physiology and behaviour which – apparently and to the best of our knowledge – have not changed at all in 10,000 years. And that led the discussion into whether the species homo sapiens sapiens is evolving, or will evolve, into homo sapiens superior, perhaps along the way through homo superior eventually to a homo scientia.
And how long could that take?
The term homo superior was coined in 1935 by Olof Stapledon in his science fiction novel Odd John which I read in my teens some fifty years ago.
Odd John: A Story Between Jest and Earnest is a 1935 science fiction novel by the British author Olaf Stapledon. The novel explores the theme of the Übermensch (superman) in the character of John Wainwright, whose supernormal human mentality inevitably leads to conflict with normal human society and to the destruction of the utopian colony founded by John and other superhumans. … It is also responsible for coining the term “homo superior”
10,000 years is about 500 human generations and is not really long enough for humans to have developed into a new species (though it has recently been observed in finches that just 2 generations – with stringent isolation – is sufficient to create a new “species”). Defining a species is not so simple, but the practical – and pragmatic – definition of a species is one where individuals (of the appropriate gender) can interbreed and produce viable offspring. Changes to the species homo sufficient to give breeding incompatibility needs significantly longer time scales. It is just a guesstimate but one reason for putting the start of modern humans at 200,000 – 300,000 years ago is that individuals from that distant past would probably be sufficiently different from modern humans to disallow successful breeding.
We do not know for sure how fast humans are evolving. Views in the scientific community are divided and range from faster than ever before, to slower than ever before, to stopped completely.
One view is that human development has neutralised the forces which have driven evolution. Certainly human development has now produced the capability for, and the practice of, manipulating our immediate surroundings. We create bubbles of habitability around us. We carry the bubbles around us not only on earth but also to escape the confines of the earth’s surface. We now have the potential to move under the oceans or even to other planets. The vagaries of weather and climate have virtually been eliminated as an evolutionary force. Having diversity is of value only when an organism has to face change. In an unchanging environment, unused diversity merely withers away. In the past it has been the uncontrollable changes to our surrounding environment which has given rise to “natural selection” and the evolution of us. In that sense, human development de-emphasises the value of genetic diversity since we maintain an unchanging environment within our habitable bubbles. Outlying genetic traits such as abilities to withstand cold or extreme heat or low oxygen pressure have lost relevance since they are not needed. There can be no “selection” for such traits when they provide no survival or reproductive advantage.
Similarly medical advances have led to the neutralisation of “de-selection” forces. Genetic propensities for disease or weaknesses are no longer “naturally de-selected” since medical advances allow and enable such affected individuals to survive, reproduce and sustain these genetic weaknesses. Physiological weaknesses which would once have been weeded out by de-selection are now no longer “weaknesses” and are preserved.
Geographic isolation of whole groups has almost disappeared. Whereas propagation remains predominantly between individuals from nearby geographical locations the occurrence of offspring from parents from distant origins is sharply increasing.
So what actually is being selected for? The short answer is that we do not know.
The three main drivers required for evolution to occur – diversity, de-selection of the non-viable and geographic isolation – have all been neutralised to varying degrees. It may not be a high probability but it is not inconceivable that the species will stagnate and individuals will regress to some mean. We could just become more and more alike. But it is much more likely that the human evolutionary drivers have just become more subtle and will only show up over longer periods. Our food habits are changing (generally softer foods) and we don’t need the same set of teeth and the same jaws that our ancestors did. Our need for long legs to hunt down prey is an anachronism. Our body size is increasing (partly nutrition, partly genetic) and this may check – and even reverse – the trend to smaller brains that has taken place over the last 500,000 years. Independent of brain size, the effectiveness of brain processes may be slowly increasing. (A smaller wrinkly brain can be much more effective than a large smooth one). The evolution of tool-making hands may be subtly changing to suit other things (bigger, more dextrous thumbs perhaps?). The disparity in the design life of our various organs was of no consequence before but are sharply in focus as we live ever longer. There is an element of artificial selection due to medical developments which was of no significance before, but is now becoming increasingly important. We are not far from the situation where the results of medical interventions in one generation could be passed on to the next. Resistance to particular diseases, for example, could potentially be induced in one generation and be passed on. Genetic engineering, if practised, could well pass on some “desired” traits to the next generation, but will also pass on many hidden, unknown traits.
Our own experience usually covers 5 generations in our c. 100 year lifetimes (grandparents to grandchildren). In evolutionary terms this is almost invisible but is certainly not insignificant. But we do not know if homo superior is on the way. There is little doubt that there will be – some 300,000 years in the future – a homo future species which will not be able to interbreed with us. But there is as good a chance that homo future turns out to be a homo inferieur, rather than a homo superior.
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