At age nineteen, after I had finished high school and enrolled at the University of Bern for my studies of law, my parents left Switzerland. My father had become the Swiss Ambassador to Ethiopia. 1974 was not only the year of my last visit to them there, two other events drew the world’s attention to Ethiopia: Haile Selassie, Emperor of Ethiopia, was removed from his throne in a communist coup d’état. And in the northern end of the Ethiopian Great Rift Valley, the Awash, the bone fossils of a female hominid were found. Worldwide, this lady became known as ‘Lucy’. The name was derived from the Beatles’ song ‘Lucy in the Sky with Diamonds’, which the excavation team played repeatedly during her unearthing. Personally, this find of our oldest ancestor did not surprise me. On my visit to Ethiopia the year before, I had taken the Djibouti train and, on the way down from Addis Ababa to Dire Dawa, I had a déjà vu. I was sitting outside on the steps at the end of the wagon and – I admit that I was smoking pot. But looking down over the vast plain with the blue mountains on the horizon, the sun on my skin, the wind in my hair, I was overwhelmed by this grand and joyful feeling. Space and time were in perfect balance, here and now was the way life was meant to be and I was part of something magnificent. Africa had nodded to me, and I had felt our ancestor’s spirit. The spot where Lucy was found was only some two hundred plus kilometers away, in Africa a stone’s throw.
The uniqueness of Lucy lies mainly in the fact that the fossil bones recovered represent 40 percent of her full, albeit small, skeleton. This is meaningfully more than the usual finds of a single jawbone, a skull, or some limbs. Lucy lived 3.2 million years ago, and she was no longer ape but not yet human. The ape in question is the chimpanzee, the primate from which she had separated some three million years earlier. Lucy was only 1.1 meters tall and weighed only 29 kilograms. But giving us skull and pelvis of one and the same skeleton, Lucy confirmed that we humans came down from the trees and became bipedal and upright before our brain started evolving. – Now, I live 3.2 million years after Lucy, I stand 1.83 meters tall, and I weigh 78 kilograms. In my life, I have sat through lessons in school and lectures at universities; I have sat at my desk in the office and sat at conference tables, dining tables, bistro tables; I have sat behind my laptop at home and sat on the sofa reading or listening to music; I have sat on high bar stools, sat in airplanes, sat in an armchair watching Liverpool FC play football on television, sat and sat and sat. Because I strived to achieve the body of Tarzan, I started doing sports early in my life. In my youth, I swam, and I played football. I was an offensive full-back with the FC Bern and, at eighteen, because I didn’t make it into the inter-regional team, I started running. As a runner, I have run the roads, hills, and forests around Bern. And even as I gave up on achieving the body of Tarzan because it became more demanding with every new Tarzan film, I kept on running. As a member of the renowned New York Road Runners, I have run the New York Marathon. I don’t play golf, but I have run the golf courses of Kinshasa, Antananarivo and Abidjan. I have run on Mt Kenya and, as my last bigger effort, I have run the Great Ethiopian Run of Addis Ababa. My very personal conclusion of all this sitting and running is that by taking us down from the trees, Lucy gave human evolution a good start. But the upright gait that followed and we humans are so proud of because we believe that it elevates us above all other animals, was a mistake. It may work for shorter persons like Lucy, but had we developed our brain first, we might have found a solution that would have spared taller people like me the back-problems I’ve been having in the last few years.
But then overall, human evolution is a messy process. Its developments are nonlinear, overlapping, sometimes dead-ended and, please note, ongoing. Trying to bring the major evolutionary steps from Lucy to ‘Homo sapiens’ – that’s us modern humans – onto a timeline, the numbers of years being order of magnitude, would give you something like this: 2.6 million years ago, the descendants of Lucy learned to use crude stone tools, and they incrementally used language to communicate. This is what made them human and justified the name of ‘Homo habilis’ for them. Homo is Latin for ‘Man’, here in the sense of human. All this happened very long before the recent sensitivities about gender, and man was still allowed to stand for all sexes. The size of the brain of the ‘Able Man’ or ‘Handy Man’ had only modestly increased over the one of Lucy.
Homo habilis was the predecessor of ‘Homo erectus’, the ‘Upright Man’, who evolved 1.8 million years ago. His body was larger, and the size of his brain had considerably increased. It is he who developed language and, on top of his tools, started using fire systematically. Fire was a life-changing feature for our ancestors. It allowed new and very efficient methods of hunting. In fact, Homo erectus is considered to be the inventor of the culinary buffet. By setting a piece of forest on fire, he could now kill and cook his prey in one single step, all he had to do was to wait and then collect. If he wanted something well done, he could cook it some more over the fire at home. He applied the cooking also to his vegetarian diet and fire provided warmth and protection in the night. His nutrition improved and now walking upright, he became more mobile. Groups of Homo erectus started migrating within Africa and some may have left Africa as early as 600’000 years ago. Arriving in Europe around 250’000 years ago, out of Homo erectus there became the Neanderthal who, as it is argued, evolved to an archaic human.
It doesn’t matter. Today, Homo erectus and Neanderthal are both extinct. Our direct ancestors as modern humans were the result of yet another step of evolution, which again occurred in East Africa. Around 200’000 years ago, out of archaic human varieties deriving from Homo erectus, ‘Homo sapiens’ emerged. Worldwide research on DNA, the thread-like chain of genetic instructions commanding the functioning and reproduction of all living organisms, shows that modern humans share 60 percent of their DNA with a banana and 98.5 percent with a chimpanzee. And whatever ‘mitochondrial’ means, mitochondrial DNA, which is inherited only from mother to mother, has been traced back to one woman who lived in East Africa around 200’000 years ago. She is referred to as ‘Mitochondrial Eve’ and is as such the most recent common ancestor of all living humans. In other words, worldwide, the matrilineal ancestor of all modern humans is this female Homo sapiens of East Africa.
The physical features of Homo sapiens moved from those of Lucy and her Homo descendants towards those of us modern humans. But the biggest change with Homo sapiens took place in the brain, the size of which had yet increased over the one of Homo erectus. Homo sapiens markedly developed the third layer of the human brain, the cortex. The cortex is a wrinkled gray matter wrapped around the mammalian brain which is wrapped around the reptilian brain. It makes for eighty percent of the volume of the human brain and the function-specific cortical areas have ten-folded from twenty of the early mammals to two hundred in humans. The cortex is responsible for the development of language and has allowed us to develop communication beyond spoken language to script and to all the modern communication technologies from radio to television to the internet. It also allows us to communicate through music and willful movements like gestures or dancing. Curtesy of the cortex, all this communication gives way to cooperation because, if the mammalian brain is the center of being, the cortex is the center of doing. But the real revolution the cortex brought about lies in cognition. Cognition allows humans to acquire knowledge and understanding through all the senses as well as through experience, reason, abstract thought, and imagination. And human cognition comes with consciousness, sense of self. If the reptilian brain is completely, and the mammalian brain partly unconscious, the cortex is pure consciousness. With its immense abilities of mental action and adapting behavior, the cortex commands the other phases of the brain. In doing so, it tends to override the emotional mammalian brain – which is not always good for us. On the other hand, when it overrides the instinctively aggressive reptilian brain, this is mostly good for us. Consciousness lets humans know who they are and what they are doing. When the chimpanzee foster mother adopted Tarzan, she recognized the situation and took the human baby as her own. It was a cognitive move, but not a conscious one. She just did what female chimpanzees do in a situation like that.
Homo sapiens shared with plants and other animals the capacity to adapt to his environment. But with consciousness on top of cognition, he had the advantage of being able to observe and understand how things came together and where he stood in the midst of everything. He figured out the primitive reptilian behavior of the crocodile of merely eating, fighting or fleeing for survival and procreating, and turned around his interaction with his predator. He started hunting the hunter and put himself at the top of the food chain. The modern human replaced the crocodile as the super predator and became himself the monster among the animals. The Nile crocodiles did not take this lightly. To this day, instinctively, they are fighting back and, in line with their natural aggressiveness, are still trying to get rid of their new competitor. In the first months of 2018, two crocodiles from Zimbabwe made international news in this fight. The first had blocked the entrance of a hospital for a full day and the other had bitten a bride’s arm off shortly before the wedding. But the new monster Homo sapiens imposed himself and both crocodiles were shot dead. In remembrance of his ancestor Homo habilis, Homo sapiens had developed the gun, and a gun is an exquisite tool in a fight amongst rivals.