Recently I completed a book, Stone Agers in the Wrong Lane, where I attempted to give a simple account of the earliest origins of life on this planet, their evolution and more particularly the Hominin lineage, that spawned our forebears and subsequently us, homosapiens. My perspective on this journey was that of a human patho-biologist, to see if I could find or recognize features, that may have influenced the origin of our degenerative diseases, in particular our leading killer, coronary heart disease.
I will now comment on events and stages in our evolution that I believe contributed. But first it would be helpful if I describe my Homosapiens Law of Change (HSLC), fashioned from Newton’s Third Law of Motion. To every homosapiens determined change, there is an opposing change of unpredicted nature, duration and extent. There are consequences that we poorly predict. Most animals do not have this problem,because they have a very limited facility to predict and ours is elementary and misleading, housed in our frontal cortex, that grew in the Rift Valley over 2-3 million years.
Near 5-7 million years ago the first Homonin and Chimpanzee separated from a large primate identified as Contestor 3, described by Richard Dawkins, in Central Africa. Its a hypothetical species at this stage, as no remains have been found. This is the first critical event in our evolution, because the Homonin gives rise to twenty one new species, where only one remains, homosapiens. The Chimpanzee, gave rise to one subspecies, the Bonobo, and both survive. What was ‘faulty’in the Homonins? Fifteen species became extinct before Encephalisation commenced with h.ergaster and h.habilis!
The Chimpanzee remains as a forest dweller as does the Bonobo, the Chimp’s spawned cousin; two species remain genetically and phenotypically unchanged for 5-7 and 2.0 million years, both occupying the Central African Rainforest. Our fore-bear starts a journey of difference, that is a feature of our Homonin lineage subsequently.Why?
Why the first members of our Homonin lineage, the Australopicenes spent increasingly more time on the forest floor, then migrated East largely, adopted an upright posture on two legs, then spawned twenty one subspecies, underwent Encephalisation, migrated extensively, supplies much data for Anthropologists, Paleontologists, Primatologists to ponder and theorise on, with limited hard evidence. You can write a book or base a career on a primate carpal bone.
Explanations for our forebears leaving the forest and standing upright are tenuous and numerous. Was there conflict with the Chimpanzee? What we do know is the Chimp in this period of 5-7 million years in this ecosystem, did not contract our degenerative diseases. No the Chimp in the wild does not have coronary heart disease. The homosapiens hunter gatherer, studied before exposure to processed carbohydrate, sugar, smoking etc., does not have coronary heart disease. Over the same period, we evolved to develop these diseases. I would have thought that with similar evidence with other mammals, like the dog and cat family, this would have been a starting point for discussion and research. Instead we had early researchers stuffing chickens, rabbits, herbivores, with fats and cholesterol, they had not consumed in a life-time and designing drugs to help!The Russians had a penchant for doing this!
Starting with the Hominins, h.ergaster, then h.habilis, h.erectus, h. hiedelbergenisis, followed by h.neanderthelis, then h.sapiens sapiens, there was a gradual increase in brain mass, confined to the ‘new brain’, the fronto-temporal region. This arose while these species occupied the extensive Rift Valley, considered by some to be a unique geological site with important elements for neurone cell growth. This was aided by a slow conversion via scavenger, to a omninivore state and consumption of animal, bird and aquatic protein with fat.This dietary conversion provided more energy for muscle, skeletal and brain growth.
The brain mass trebled in size in four million years, from h.ergaster to h.sapiens. The physical size and skeletal mass increased also in each species like a shadow. By committing to an omnivore nutrition, the consumption of fats of all types, especially marine polyunsaturated fats from aquatic sources and protein, were potent nutritional growth factors in this instance. We see this in malnourished homosapiens, usually attached to a carbohydrate diet, such as most of Asia. The large herbivores we are familiar with, have an extended range of nutritional items. The Kenyan Gorrilla has over 200 items and some hunter gatherer, over 500 items!
During this tour through our evolution the change in the nature of our nutrition in the Rift Valley, that potentially may have contributed to Encephalisation, is persuasive. My contribution was, growth was confined to the fronto-temporal–parietal structures, simply because this was where a very satisfactory blood supply, near six times that of the posterior supply, had evolved before Encephalisation occurred. During this time, some four million years, our closest relative genetically, the chimp, puddled along unchanged. ie habitat or nutrition. Their skeletal size and brain mass, unchanged from that of four million years ago.
Our twenty one Homonin fore-bares experienced regular extinction and some overlapped their time on Earth; now there is one left. Why? The Chimp is still here, provided we let them be. On this tour I calculated assessed time on the planet by the Austalopithecines was near six million years longer than the Hominid species that followed. As your brain gained mass, you did not survive as long as previous species! At the same time migration of h.habilis, h.erectus, h.hiedelbergenisis, h.neanderthalis co-incided with Enchephalisation. Yes,tool design expanded with hunting, floatation in rivers and migration in Asia arose too.
The use of fire, tide dams for fish, smoking food, artwork, speech has been accepted as consequences of Encephalisation. But why did each species perish, become extinct?That is up for debate, but I believe we have ample evidence, why this species homosapiens, is and will accelerate us to extinction. It’s a lineage feature, its ‘in our genes’! It’s a matter of when and whether we can postpone the date!
It seems to me, we for the first time have been able to collect our short history and now after analysis propose solutions. At the Neolithic period we appear to have made a voluntary choice of change and for the first time embarked on ‘producing’, modifying nutrition, when before we selectively used what was available. More recently commercial and financial systems in medical ignorance, drove an industry that I believe professionally, have contributed to degenerative diseases and our leading killer coronary heart disease.
From the Neolithic period, I can identify the features of the journey to the pandemic of degenerative diseases today, in the affluent and non-affluent world. This was voluntary and gives us a clue of how Encephalisation is a poisoned chalice and perhaps how our fore-bears perished and the Chimp remains unchanged!
My Law of Change applies to the decisions and practices ,I believe have contributed to our plague of diseases and the leading killer coronary heart disease. It appears it applies to most things we do. Try ‘splitting the atom’ by a NZ country boy Sir Ernest Rutherford, who indicated this process would, could not be used in WOMD. Knowing the evidence based frailties, inadequacies of homosapiens, this could be our most prescient way to extinction.
If we applied the criteria we expect with a new drug to the seed flours, sucrose, fructose and vegetable oils, would they pass, survive? This is not a democratic, human rights issue, its about an epidemic that has afflicted more humans than all the epidemics ever! Arguably between half and one billion have died prematurely already.Its a pandemic, the largest ever. If we could prove Cytomegalovirus or another infective virus, say H23 N17(hypothetical) was responsible for the initial lesion, we would have the politicians declaring a state of national emergency to the ‘plague’! Anything to avoid our responsibility, contribution.
We have been born into a species culture that seriously believes we are a ‘superior’ species. Near 2-300,000 years ago our brain was the largest it has been. We were hunter-gatherers well adapted to our ecosystem in the Rift Valley, behaving as all animal species do, surviving and reproducing. Then we commenced the processes to change our life practices, nutrition, shelter and transport.I am not aware of any reason to migrate from the Rift Valley, starting between 70-100,000 years ago. There are well surviving tribes in East Africa today that remained with a hunter-gatherer life practice. I understand you may find a Coca Cola bottle there now sometimes. Has the migration to occupy the planet been in the planet’s or our best interests?Has Encephalisation, brain growth, not been a poison chalice accelerating us to extinction.
Dr.Lindsay A. Green FRACP. FCSANZ