1. From where we have come? It is important to the question of where are and where we might be going in out lives? It is common to encounter the false view that we were once apes in the jungle and then something odd happened which gave rise to cave paintings, pyramids, writing and then along came the Greeks who started Western Civilization.
2. Yes it all did begin with the evolution of the great apes. This occurred over millions of years through a very complex process that included isolations, interbreedings and hybridization. In general the human evolutionary line separated from our closest living relatives, the surviving chimp line, between 7 and 4 million years ago. The chimpanzee species (Pan troglodytes) are well-known in modern culture. A lesser known surviving species, the bonobos (Pan paniscus) separated from the Homo evolution line 2-4 million years ago. Present day humans are not that differently genetically from our co-existing chimp cousins. Humans share between 98.5–99.4% of their genetic code with chimpanzees and 98.7% of their genetic code with bonobos (http://news.sciencemag.org/plants-animals/2012/06/bonobos-join-chimps-closest-human-relatives).
3. Behaviorally we can look to our living animal cousins to gain some insights into how our common ancestry reflects on how we behave in today’s world. One key distinction that sets Homo sapiens apart from chimps and all other animals is our dependency on sedentary agriculture activities for gaining our nutrition. We justify our agriculture-based system by seeing “challenges” in the life-styles of our distant chimp relatives. Much has been made of the “fight for survival” – emphasis added. But there is evidence according to Ryan and Jetha (2011) that chimps have survived for millions of years as relaxed gatherers of food without much aggression. In fact they point out that our false impression of prevalent aggressive chimp behavior has resulted from human manipulation of their feeding habits by presenting them with locked boxes brimming food. Additional lifestyle “challenges” beyond physical aggression in chimp behavior most likely results from our observation of chimps in highly artificial environments of zoos and cages. Bonobos in the wild have been seen to be playful, sexually active, relatively long-lived and non-aggressive. So humans are likely to have come from a much more relaxed and robust lifestyle of the chimps in the wild.
4. In the evolutionary history of humans, there have been many unsuccessful hominini species that have died out over time see http://humanorigins.si.edu/evidence/human-evolution-timeline-interactive. One thing is for certain, humanoids and chimps were primarily gathers of food for millennia - these species survived without agriculture. While the surviving chimps and bonobos continue to live that relaxed style of life in their natural habitat today, humans do not. Today most, but not all, Homo sapiens live through the graces of agriculture and highly organized societies. When and how did things change – and is it an improvement? Is a capacity for higher development – as represented in art, deliberately constructed structures, physical representations of the sun, moon, planets and stars – that is, the higher awareness - dependent on sedentary agriculture?
5. Once the evolutionary lines began split between chimps (genus Pan) and humanoids they co-existed for millions of years in Africa. Homo heidelbergensis was the most recent humanoid ancestor identified as established about 700,000 years ago in Africa. They had a brain case equivalent to modern day humans; they were 5 to 6 feet tall, with some populations reaching 7 feet in height. There is evidence of 500,000-year-old spear points being fashioned and used by this species indicating hunting activities. They may have buried their dead. With the use of spear points, these humanoids were the first hunger-gatherers – or as Robert Schoch suggest as more correct they were gatherers-hunters as most of their nutrition likely originated from the gathering activities rather than the hunting activities. It is becoming more and more accepted that gathering-hunting is an effective life style in suitable environments (Ryan and Jetha 2011). Its persistence over 100,000’s of years is evidence of this. The West coast Canadian Haida nations are just one clear example of a present day gatherer-hunters culture establishing sedentary lifestyles and supporting a highly sophisticated culture.
6. Returning to our evolutionary line, some of the H. heidelbergensis members managed to migrate out of Africa between 400,000 and 300,000 years ago. A number of them moved northwest into Europe and eventually evolved into the well-known Neanderthals (Homo neanderthalensis) around 3 to 4 hundred thousand years ago in Europe. Although shorter in stature, H. neanderthalensis were more physically robust, had large brow-ridges, a slightly protruding face, and lack of prominent chin. They had a brain that was slightly larger than most modern day humans. They build complex structures for living in and hunted with sharpened points. Recent research supports their use of eagle talons to make jewelry 100,000 years ago. Studies have indicated that H. neanderthalensis survived for 250,000 years before dying out around 40,000 years ago. We share 99.88% of our genetic code with Neanderthals.
7. While Neanderthals were living successfully through the challenges of the ice age in Europe, Homo sapiens were slowly evolving and developing from the H. heidelbergensis remaining in Africa. H. sapiens separated from the H. heidelbegensis population around 200,000 years ago coincident with the extinction of H. heidelbergensis. H. sapiens have the smallest brows of any known hominid, are taller and more graceful, and have a flat face with a protruding chin. On average H. sapiens have a brain size between the smaller H. heidelbergensis and the slightly larger H. neanderthalensis.
8. Typical of the process of evolution, human evolution involved environmental pressures and species responses. It has been suggested that there was an evolutionary bottleneck of H. sapiens 70,000 years ago with the total population being reduced to less than 30,000 individuals – and possible much fewer. The climate was highly variable and this bottleneck may have given rise to a small population of genetically adept individuals, but we were a “species at risk” for a time. We were more or less genetically and physically modern by the end of this bottleneck.
9. Culturally, we see the first evidence for modern gather-hunters who created art, paint and jewelry on the coasts of South Africa from 100,000 and 70,000 years ago. In Blombos Cave, South Africa, H. sapiens produced cave art, produced spear points and ocher paints. It is unclear whether these populations developed as a result of the unlimited supply of high quality marine food rich in omega-3 fatty acid, but they certainly could not be considered food limited in that environment. They had great luxury in their food sources which would free up their time for other interests and development.
10. H. sapiens made their way up through the landmass of Africa. Although it is commonly believed that they exited Africa only about 60,000 years ago, there is some evidence in the Middle East that they were on the move out of Africa more than 100,000 years ago (CBC, 2014). H. sapiens moved into Europe, Asia and the Far East as the last ice age weakened between 45,000 and 43,000 years ago.
11. As H. neanderthalensis died out around 40,000 years ago then that the two different humanoid populations co-existed in Europe for at least 5,000 years and maybe for millennia (CBC, 2014). There is strong evidence that by 55,000 there was inter-species breeding and hybridization among H. neanderthals and H. sapiens in Israel. Genetic analysis also shows interbreeding with another huminoid non-African co-habitant species Denisovan (https://en.wikipedia.org/wiki/Denisovan) We were not that different from one another.
12. In my next blog I will explore our continued cultural evolution following Andrew Collins (2014) excellent book related to the exciting finds at Göbekli Tepe, Turkey, dated to 12,000 years ago.