Throughout modern history there have always been refugees and migrants, people fleeing wars or famine, looking for a better life, or just satisfying their own wanderlust. The genus Homo – both sapiens and their ancestors – has always been the wandering kind. But unlike any other species, Homo species probably all talked about their migrations. And their conversations about travel made the trips more enjoyable. Humans don’t migrate like other mammals. We sapiens plan our trips, review them, celebrate them and lament them. And erectus seems no different, from what we can tell from the fossil record.
This conscious movement to the unknown was but one of the cognitive capabilities that emerged in humans on their long path to becoming sapient. Their new-found consciousness was a state of mind that exceeded mere animal awareness. Gradually our ancestors’ consciousness came to include self-referential reflection: not only did their thinking include ‘I am aware of x’ but also ‘I am aware that I am aware of x’. This is ‘conscious consciousness’ and it would have facilitated their travel as well as their thinking about the symbols that were already emerging from the growing complexity of their cultures. Homo species in all probability began their perambulation with self-conscious purpose. Erectus would have been the first creature in history to be self-conscious. And the first to imagine. (Imagination is the knowing consideration of ‘what is not but could be’.)
Homo erectus would have initiated the sharing of values that is unique to human societies. Social roles began to emerge as communities discovered that different community members were better at some things than others. These ancestors began to remember and to organise the knowledge they were gleaning from the world around them and from each other. And they taught their children these things. This is inferable from the ever-improving tools, homes, villages and societal organisation that have been found in the fossil record. Humans were getting smarter. They were becoming cultured. They had crossed the communication-language threshold.
There were changes in Homo erectus that no other species in the history of the planet had undergone. Erectus’s achievement of self-conscious cognition quite possibly enabled them to (eventually) talk about, characterise, contextualise and classify their emotions – love, hate, fear, lust, loneliness and happiness. Our ancestors in all likelihood also began to keep track of their kith and kin on their travels. And this growing knowledge, as it emerged from their evolving culture and travels, would have eventually required them to invent language of some sort (with their relatively enormous brains). And increasing culture placed evolutionary pressure on erectus to evolve ever more effective and efficient linguistic abilities, accompanied gradually by the brains, bodies and vocal apparatuses necessary to exploit those abilities fully. At the same time, at the interstices of culture and language, erectus would have been developing what can be referred to as ‘dark matter of the mind’ – tacit, structured knowledge, prioritised values and social roles. Dark matter is crucial to the interpretation and arrangement of human apperceptions (experiences that affect our development, stored in our unconscious that create individual psychologies).
The emerging psychologies of Homo erectus would have interacted with their community to produce culture. Erectus followed the more hospitable and passable swathes of East Africa until they emerged from the continent, initially in the Levant and then on across Eurasia and to islands across the sea. They were the Argonauts of the Pleistocene. And as they arrived they were more sophisticated than when they left. They were also better fed.
Hunting prowess and the advantages of a meat diet fuelled erectus travel. The hunt provides much more than fat and flesh. Hunter-gatherers eat the skin, bones and offal. They consume nearly the entire animal head to toe. They eat the bones by splitting them and scraping out the marrow. Then they shave bone fragments off that are so thin that they can be eaten without difficulty or they are boiled and consumed. And then, after eating this large quantity of animal protein and calcium, they can rest for a day or two before needing to hunt again, depending on the size of the animal killed. Like modern hunter-gatherers, erectus also controlled fire. It not only killed better than other creatures, it ate better and healthier. And it transformed its body and its brain. Fire would have been tremendously helpful during the trip, allowing them to travel further in a day, chat around the campfire at night and build strong ties of community.
Anyone who has accompanied hunter-gatherers as they pursue game for several miles without rest knows the joy of talking about the hunt at night around the fire. Sometimes they sleep near their kill because they are too tired to make their way back to their village. Then, the next day, after again eating very well, erectus bands might have bundled up their leftovers with vines or have simply tossed large portions of the animal, such as a leg or hindquarter, across their shoulders as they headed back to their families. If their families were already with them, perhaps they remained a bit longer near the latest kill site. They may have tarried a day or so, then explored further around their new campsite, after consuming all of the meat from the previous day. Perhaps they relocated their village to the site where they successfully killed the game, especially if it had more abundant edible plants or more game.
How easy was it to travel around in Africa at the time of Homo erectus? During this period, roughly 2 million years ago, Africa was climatologically very different from today. The so-called ‘Sahara pump’ was active then. The current Sahara desert was then non-existent. Instead, all of North Africa was covered in lush forests that stretched across the Middle East and on through Asia. Flora and fauna were rich throughout large swathes of the world that are today barren deserts. This ecological-climatological fecundity dramatically contrasts with today’s North African climate and it clearly supported the exploration and nomadism of Homo erectus. Major changes in human genes were also happening at this time, changes that I suspect would have facilitated the expansion of Homo erectus’s geographical range, even without the Saharan pump.
Erectus was truly marvellous. But in spite of the admiration they richly deserve, these people were not the equals of Homo sapiens, not even of neanderthalensis. They were simply the first habitually upright hominins and the first humans. They were the first interpreters of their own visions, as they were the first bearers of culture and the earliest storytellers of our planet. They were the progenitors of both neanderthalensis and sapiens. Their skulls and bodies were becoming more modern, though they still had prognathous jaws, making them look somewhat ape-like (Figure 5).
What is really known about Homo erectus? Did they really have language or were they just grunting cavemen? Like most areas of human endeavour, ignorance outstrips knowledge. There is much to learn about these ancestors before they and their role in the evolution of the genus Homo is fully understood.
On the other hand, less is known than one would like about a lot of things that researchers hazard informed hypotheses about. So this should not stay anyone from considering ideas that are supported, however shakily at present, by the facts. For whatever reason, a subset of the erectus people decided to leave Africa about 1.8 million years ago. Their travels began only a couple of hundred thousand years after they first appeared. Not long after that (in geological time, very quickly: only about 200,000 years), confirmed evidence shows them in South Africa, the Middle East, modern-day Georgia, Europe, China and Java.
Homo erectus evolved in the Pleistocene from australopithecines. Their bodies got bigger. Their brains got bigger. Their societies grew more complex. Their technology developed quickly. Why did this transformation emerge during the Pleistocene? Why not later or earlier? Is this a mere coincidence? Most think not. The Pleistocene posed the problem of survival as it had never been posed before for hominins. Its rapid climate variations, advancing and receding glaciers, changes in flora and fauna were among the challenges it forced hominins to adapt to.
Figure 5: Homo erectus (artist’s impression)
According to some classifications, there were, soon after and b
efore erectus, other species of Homo co-existing or existing in close succession – Homo habilis, Homo ergaster, Homo heidelbergensis, Homo rudolfensis among others. But, again, most of these various species of Homo are ignored here, with the focus kept on Homo erectus, Homo neanderthalensis and Homo sapiens. Most other Homo species are murky, maybe nothing more than variants of Homo erectus. However, the story of human language evolution changes in no significant way, whether erectus and ergaster were the same or different species.
Remaining with this simplified inventory of species of Homo, Homo erectus was in all probability well on the way to inventing language by roughly 1.9 million years ago. They used tools. This brain size resulted from many pressures – the advantages of improving tools, the need for better communication to keep track of social relationships, travel and the need to cope with a rapidly changing environment. As the climate became more arid and colder in East Africa, erectus trekked to the south of the continent.
It is no coincidence that the greatest changes and innovations in human physiology, cognition, sociality, communication, technology and culture (dwarfing any of today’s inventions and developments) occurred during the Pleistocene. Glacial sheets covered the northern hemisphere many times during this period. Some pre-Homo hominids adapted physiologically to the greater aridity of the environment. Paranthropus, a genus of ‘robust’ australopithecines contemporary with erectus, grew bigger teeth, with thicker enamel in order to eat seeds that became larger and harder to crack during this time.
But erectus relied on culture to solve problems posed by their volatile environment. Instead of their teeth, erectus used rocks for cracking seeds, thereby adding cultural pressure to evolve more and more intelligence to make better tools. This was what I call the ‘first cultural revolution’, where our ancestors changed culturally in order to answer the ever new challenges of their environment.
It was during this time, over 2 million years ago, that a common set of stone tools, the Olduwan tool kit (flaked rock tools named for the site of their earliest discovery, by the Leakeys in the Olduvai Gorge), first appeared in the archaeological record. This tool assemblage may (or may not) have been used by australopithecines initially. Similar but non-identical tools can even be used by chimpanzees and other non-human apes (in ways quite distinct from human usage), though a great deal of practice is required. Regardless of its first users, however, this tool kit was widely employed by erectus and other Homo species. The arrival of tools signifies that culture is beginning. And the birth of culture has implications for language evolution and physiological adaptations during this time.
Figure 6: Olduwan tool kit
The Olduwan tool kit shown in Figure 6 was made by a process of flaking, which began rather simply but eventually led to quite complex skills.
Though occasionally it is said that animals such as otters, chimps and orang-utans have ‘culture’ based on their use of tools, real culture is far more than merely this. Likewise, culture is more than the transmission of tool technology or other knowledge from one generation to another by imitation or overt teaching. Culture attaches values, knowledge structures and social roles to humans and their creations. This means that even tools have meaning. Because of this they bring to mind for the member of a culture the tasks they perform, even when those tasks are not currently under way. A stone axe on the ground can elicit memories of the times they have been carried on trips. It can also bring to mind a previous user.
Cultural implications thus surpass mere tool use in cognitive complexity. When an orang-utan uses a stick as a spear to catch fish in Borneo, or a chimp uses a chair to climb up over a fence, or an otter uses a stone to open a shellfish – even if their offspring learn to use these from them – this does not mean that they possess culture. They are using (perhaps even transmitting) tools in the absence of culture. Impressive as tool use is, culture goes beyond this by contextualising artefacts. This is what enables tools originating in a particular culture to evoke meanings even when they are not being used. A member of a culture that uses shovels or scissors knows what shovels or scissors are for even in the absence of their associated activities. The tools alone will bring those activities to mind. Outside of culture, tools evoke no abstract connections to values, social roles, or knowledge structures. One can tell the difference only by examining the evidence that tools emerge from a system rather than from a one-off or idiosyncratic invention, as perhaps a chance usage by a single family or individual. We might question whether the tool plays a part in distinguishing social roles or relative to other tools, or attempt to determine its value relative to other tools of the culture. Is it used only by some people or by everyone? Does it have a specialised purpose?
Other evidence of incipient culture among Homo erectus populations is one previously mentioned, namely that erectus adapted physiologically to a relatively rare way of life among animals – pair-bonding – a social structure in which males and females mate long term wherein the male feeds and protects the female and their offspring in exchange for near-exclusive sexual access. Pair-bonding is inferred not only from the archaeological record of erectus villages but also from smaller erectus canine teeth and reduced sexual dimorphism between males and females. Pair-bonding plus tools is evidence for family units and cooperation.
This view of human cooperation in erectus is strongly supported by the archaeological record. As erectus wandered through the Levant, near the Jordan between the Dead Sea to the south and the Hula Valley to the north, they came to stop at the site known today as Gesher Benot Ya’aqov. At this site, going back at least 790,000 years, there is evidence for Acheulean tools, Levallois tools, evidence of controlled fire, organised village life, huts that housed socially specialised tasks of different kinds and other evidence of culture among Homo erectus. Erectus may have stopped here on the way out of Africa.
Erectus technology was impressive. They built villages that manifested what almost appears to be central planning, or at least gradual construction under social guidance, as in Gesher Benot Ya’aqov. This is clear evidence of cultural values, organised knowledge and social roles. But such villages are just one example of erectus’s technological and organisational innovation.
Another may be seen in the routes they followed. As specialists have mapped out the travels of Homo erectus around the world an interesting observation comes to light – erectus seems to have deliberately travelled to geologically unstable areas. Erectus followed a route known as the Plio-Pleistocene Tethys (the former coasts of an even more ancient ocean), which provided a natural geographic path, along with geological instability.*
Whether it ultimately turns out to be correct or not, the idea that geology played a major role in the routes of the migration of Homo erectus, rather than simply random wanderings about the earth, offers clues to the species’ thought processes. All humans make decisions and they marshal evidence for those decisions. It would be extremely surprising if Homo erectus did not have reasons for going left or going right as they travelled. Though culture also played a role, the Plio-Pleistocene Tethys offers a simple possibility – namely that erectus followed the ‘lie of the land’. There were geological conditions favourable to the route that erectus chose. If this is correct it is an interesting finding. However, before we can definitively interpret the routes of erectus as based on culture and cognition vs simple hunting like any other animal, we would need to compare their routes of migration to those of other animals that left Africa. And then we’d have to determine whether erectus was simply following other animals or whether they were being guided by hunger rather than cultural values or knowledge structures.
However, the possibility that erectus was travelling based at least partly on culturally guided or otherwise intelligent decision-making is supported by other finds in the record. One of the greatest surprises in archaeological history – and there have been many – was the discovery of Acheulean tools on the Indonesian island of Flores in 2004. This find was preceded some
what by a discovery in 1957 by Theodor Verhoeven, a Dutch archaeologist and missionary, of bones of Stegodontidae, an extinct family of Proboscidea (relatives of mastodons, mammoths and elephants), on the same island. The stegodonts, like modern elephants, were very good swimmers. Elephants have been observed to swim for as long as forty-eight hours, in a herd, across African lakes. They are known to have swum as far as thirty miles (forty-eight kilometres) at sea (which is further than the distance to Flores would have been 750,000 years ago).
Flores sits among the lesser Sunda Islands of eastern Indonesia. The fifteen-mile (twenty-four-kilometre) strait separating Flores from the closest land, the source of the Stegodontidae, would not have presented a great swimming challenge to the large mammals, who pursued floating plants across the strait. But the tools later discovered near charred bones of these creatures do present an enigma. How did they get there? These tools are nearly 800,000 years old. And there is no period during which the island was connected to any other land. It has always been isolated by deep water. Erectus somehow got to Flores. How?
Unlike the Stegodontidae, they could not have swum there. Even had they spotted the island on the horizon and decided to visit, the currents would have made swimming there impossible. The greatest waterflow in the world is known as the ‘Pacific Throughflow’, and it flows around the islands of Indonesia, including Flores. These currents would defeat all but the most elite athletes. Yet there is evidence of a relatively large erectus population on the island. A founding population would need to include a minimum of fifty individuals. And it is unlikely that they all set out paddling logs or attempting to swim across treacherous currents, even though they may have witnessed stegodonts doing such a thing. They must have had a motive to go, certain that there would be plenty of food there.
How Language Began Page 7