Welcome to the first instalment of Rest is History’s series on world history. Over the course of the series we will explore how in a mere 15,000 years humans went from hunting and gathering to putting man on the moon. But first, before we tell the stories that make up world history, it is useful to understand where and how it all began: where our human story, the story of all of us, begins.
The Evolution of Man
Modern humans (Homo sapiens) are just one of a group of animals known as hominids which were the earliest humanlike creatures. Archaeological evidence suggests that hominids speciated (separated) from other primates some time between 2.5 million and 4 million years ago in eastern and southern Africa. Though there was a degree of diversity among the hominid family, they all shared one common trait: bipedalism.
Hominids continued to evolve and develop unique characteristics with their brain capacities increasing and approximately 2.3 million years ago, a hominid known as Homo habilis began to create and use simple tools. Around 1.8 million years ago, some hominid species began to migrate out of Africa and into Eurasia where they began to make other important advances to the human story such as the ability to control fire.
To get an idea of the vast timescales we are talking of here, the earliest hominid migrations out of Africa took place so long ago that they occurred almost six times earlier than modern humans have even been around!
Although there were once many variations of hominids, only one remains today: us, Homo sapiens. It is estimated that humanity, in its modern iteration, has been around for at least 200,000 years. The speciation of Homo sapiens out of archaic human varieties derived from Homo eructus is estimated to have taken place between 300,000 and 200,000 years ago.
A Migrating Species
The dispersal of early Homo sapiens from east Africa began soon after its emergence, as evidenced by the Jebel Irhoud fossil discovery in western Morocco near the Atlantic coast. These finds have been dated at around 300,000 years old. There is also indirect evidence to suggest that modern humans had made it as far as west Asia by 270,000 years ago.
Concrete evidence suggests that our early ancestors began to migrate out of Africa sometime between 70,000 and 100,000 years ago and began populating parts of Europe and Asia. Sometime between 35,000 and 65,000 years ago humans reached the Australian continent using simple boats. These early Australians are the ancestors of the Aborigine people. Around 35,000 to 30,000 years ago man had migrated as far as north eastern Siberia and some of these crossed into North America via the Bering Plain some 20,000 to 15,000 years ago. The Bering Plain intercontinental land bridge appeared between Siberia and Alaska due to the drop of sea levels by up to 137 metres (450 feet) during the closing stages of the last ice age. From here, Homo sapiens was able to head east and south, populating both the North and South American continents. Humanity had become a global species.
The question of why our ancestors decided to leave their homes in Africa remains unanswered but scientists, archaeologists and anthropologists have theories. It is estimated that the development of language occurred between 60,000 and 100,000 years ago. This evolutionary breakthrough allowed early man to make plans, solve problems and organize more effectively. We cannot be sure of the exact reasons that Homo sapiens first migrated from the African continent, but it likely correlated with a depletion of resources, particularly food, in their regions and competition for those sparse resources with other Homo sapiens as well as other hominids. Another theory posits that Homo sapiens migration was due to curiosity: they instinctively wanted to know what was beyond their environment. It is quite easy to picture really:
Ugg: ‘What is behind that mountain, Thug?’
Thug: ‘I don’t know Ugg. Why don’t we go find out?
Whatever the reason may be, once humans had the ability to communicate these concerns and make plans then they could collectively evaluate whether the pressures in their current situations outweighed the risks of leaving home to find a new one.
A consequence of human migrations into new regions of the world was the extinction of many animal species. In the modern age, when we think of human induced extinction we tend to think of the dodo or the numerous animals currently on the brink of extinction due to habitat loss and hunting. The truth is, we have been doing this for millennia. By 11,000 years ago, human hunters in the Americas had seemingly played a huge role in the extermination of 135 species of mammals including three quarters of the larger ones (think mammoths, giant sloths, mastodons). These extinctions occurred rapidly too; it is thought no more than a few hundred years. This trend was not isolated to the Americas neither. Similar mass extinctions occurred with the arrival of the aboriginal people in Australia and Polynesians in New Zealand. In both cases humans were directly responsible for wiping out easily hunted species. The large vulnerable marsupials were the main sufferers in Australia with up to 90% of the larger species being wiped out within 5,000 years; whilst large, flightless birds were driven to extinction in New Zealand following the arrival of humans in the 10th – 13th centuries CE.
It was not just other genus of animals that Homo sapiens had a hand, either intentionally or not, in the extinction of. Next, we shall look at why it was us and not some other bipedal offshoot of Homo habilis who came to dominate the planet.
The Wise Man Triumphant
First off, I think that it is important to understand just what Homo sapiens translates into. As some of you will know Homo is the name given to the genus (or biological classification like feline for cat or equine for horse) that encompasses modern humans and some other species that are classified as ancestral or closely related to modern humans. It is Latin for “man” whilst sapiens translates to “Wise”. The term was coined by, Swedish zoologist, Carl Linnaeus in 1758.
Do we deserve such a distinguished and enlightening title? It may seem hard to see how, with the popularity of trash television and an ever-increasing number of internet trolls spewing hatred and stupidity onto the internet, but the simple answer is yes. Yes, we do. It is because of our greater brain capacity that we even have the television to idle away our time or the internet to heatedly debate strangers on topics that we don’t really care about. We are the only hominid to have developed these wonders, we are the only hominid left standing. How did this happen? What differentiated us from our early cousins?
The consensus is that our ancestors were more adaptable than their ancient counterparts, meaning that we were not restricted to a single environment but could survive, thrive even, in many environments. Homo erectus was the first hominid to leave the ancestral continent, making the journey around 1.8 million years ago. Homo sapiens would still not speciate for a further 1.5 million years at this point so Homo erectus had plenty of time to explore and populate Eurasia.
When the later evolving Homo sapiens dispersed from Africa and journeyed across Europe and Asia they would have crossed paths with members of the Homo erectus species. No one can know for sure how these first interactions would have gone down but there is some evidence to suggest that a degree of interbreeding occurred. However, some argue that this is where the co-operation ended and Homo sapiens outcompeted their lesser evolved cousins for resources (Go Us!). They occurred together and used the same resources, so it is quite plausible that Homo sapiens could have caused the extinction of Homo erectus. This scenario where the later evolving species replaced the earlier evolving species is known as the replacement hypothesis.
Complicating the picture further was the Homo neanderthalensis, more commonly known as the Neanderthal. Genetic evidence suggests that Neanderthals were more closely related to modern man having diverged from him between 800,000 and 500,000 years ago before they too left Africa. Once again, there is evidence hinting at interbreeding between the two hominids in Europe. Homo sapiens may have outcompeted Neanderthals for resources just like they did with Homo erectus.
All of this occurred during the Pleistocene ice age when Europe was experiencing bouts of extensive glaciation. As noted above, Homo sapiens were more adaptable to changing environments and so it is possible that climate change was the actual cause or perhaps a contributing factor in the extinction of Homo erectus, Homo neanderthalensis or both, whilst modern man simply adapted to these changes.
Man’s Best Friend
I cannot write a piece on early man and his evolution without mentioning his best friend: the domesticated dog and his evolution. Very little about the causes and context of dog domestication are known. It is known that domestic dogs evolved from a group of grey wolves; and it is believed that these wolves encountered European hunter-gatherers sometime between 18,500 and 32,000 years ago. Other scientists believe that the first domestication occurred as recently as 14,000 years ago, whilst others place it at over 30,000 years ago. Some believe it first occurred in the middle-east, whilst others think it happened in the far east…. In other words, no one has a scooby.
Okay, so we know what we don’t know about canine domestication then. We know that we don’t know the place or the time of the first domestication, but do we know why it happened? I’m afraid that we do not know that either. What I do know, however, is that there are several theories and I know which one I believe to hold most weight.
Early wolves would, as scavengers, be attracted to the bones and refuse dumps of human campsites. The wolves would recognise specific human groups as their own and would protect the territorial range from strange wolf packs and other animals. These early feral adoptees became tame wolves, dependent upon the humans for their source of food and became less fearful of humans than most wild wolves. This trait may have been heritable, making these wolves more susceptible to being domesticated.
Whatever the cause and wherever and whenever it happened, canine domestication was very important for the human story. If you remove domestication from the human species then there would probably only be a couple million Homo sapiens on the planet, maximum. Instead, we have over seven billion people, environmental manipulation, climate change, the internet and space travel. Human domestication has influenced the entire earth and it all started with the dog. For most of human history, we were not that dissimilar from the other primates that roamed the planet. We were manipulating our local environments but on no bigger scale than any other large mammal. And then we go into partnership with a group of wolves: they altered our relationship with the natural world.
And the Rest Is History
Next time we will look at how these adaptable Homo sapiens went from hunter-gatherers to farmers and the consequences of this agricultural revolution.