The inspired insights of Charles Darwin irreversibly changed our world, shedding light on the origins of life and challenging religious orthodoxy. His Theory of Evolution can hardly be questioned in the light of fossil evidence and few deny that life forms have progressed from the simple to the complex including ourselves over billions of years. Darwin perceived that Natural Selection is the `engine` of Evolution selecting those reproducing individuals of a species best equipped for survival in a hostile environment. Populations of a species differ widely in characteristics from the `norm`, be it in height or prominence of nose in the human species extending to ambition or indolence or in an insect species to resistance to pesticides. From natural variation are selected for survival those with most favourable attributes. Thus a species is refined to fit the requirements of an environment but profound changes in a species depend on sporadic changes in gene structure resulting from mutations in the germ cells of a reproducing life form. Such changes may be accelerated by radiation or other ill- defined environmental factors either favourable or unfavourable to the survival of the progeny which in turn determine the likely prevalence of the new gene in the species. The genetic makeup is known as the genotype which determines the apparent manifestation or phenotype. Most mutations are unfavourable, many are neutral or irrelevant and do not persist. Favourable mutations are much rarer. Major changes in a species require a series of complementary new genes and for such a constellation to assemble becomes statistically very unlikely requiring many thousand or even millions of years to become a reality.
Mutations are more frequent in animals producing thousands of fertilised eggs during short lifespans with a rapid turnover of generations such as fruit flies and many insect, fish and amphibian species. Humans are generally capable of producing no more than ten children over a reproductive span of fifty years hence human evolution may be expected to be a very desultory process. Africa, more specifically the Great Rift Valley, is regarded as the cradle of humankind from which Homo Erectus emerged 500,000 years ago and migrated across the still existing land bridge between Ethiopia and Southern Arabia to lightly populate the Near East and Europe. H.Erectus was much like ourselves, walked upright, utilised fire, made crude weapons, hunted and probably had the rudiments of speech but could not throw effectively, lacking the ability to rotate the forearm. He was well adapted to thrive as a hunter- gatherer in the African Savannah. Homo Sapiens evolved from the same African cradle 200,000 years ago in two subspecies… Neanderthalensis, a cruder, stockier, supposedly less innovative version than the newer current `model` Sapiens Sapiens… our- selves. Neanderthalensis preceded Sapiens Sapiens across the same land bridge into the Near East and Europe perhaps 90,000 years ago. Whether he found remnants of H.Erectus still surviving the Ice Age we do not know but 10,000 years later Sapiens Sapiens followed and annihilated or absorbed Neanderthalensis. H.Sapiens also spread from the Near East into Asia, and Oceana and only latterly into Australasia and the Americas.
The qualities which set us apart from H.Erectus are far in excess of the demands of the African Savannah and could not have developed from favourable mutations over a mere 150,000 years between the supposed accession of H.Sapiens and the exit from Africa. The apparatus for speech of the quality we enjoy required huge anatomical adaptation in the larynx and coordination between the vocal cords, tongue, facial and respiratory muscles to create the nuances of tone, volume and timbre controlled by a highly developed speech centre in the brain and extensive neural connections. This complexity would require many `good` mutations fortuitously arriving in time to complement the whole. The development would be impressive over a million years but virtually impossible to explain in Darwinian terms over a period of 150,000 years. No less remarkable are the uniquely human qualities which were already developed 80,000 years ago when H.Sapiens stepped out of Africa. The evidence for this consists of attributes shared by all of humanity, by all races, from all continents which could not have evolved separately since the exodus from Africa a mere 80 thousand years ago. We share the same body language and facial expressions, a capacity for abstract thought, are able to share humour and engage in song, dance and the arts. We are able to learn the language of `the other` and amongst all groups there are those with exceptional capacity to invent and excel in various fields… literature, architecture, medicine, engineering and extend the boundaries of knowledge into the realms of astrophysics and cyber communication. These abilities far exceed the skills necessary for humans to survive as hunter-gatherers in the African Savannah. How may we then explain the ascendancy of Sapiens? I cannot. Awaiting an explanation we should not be content with hasty `fillers` nor gloss over the anomalies as if these do not exist.
Reflections of a Sceptic 