Friday, April 08, 2011

Lost Civilisations: How Plausible?

South Africa 2010


Stories of secret or lost civilisations have captivated our imaginations for centuries - from Atlantis and Shambhala in the Old World, to the search for El Dorado in the Americas. Hard evidence for the existence of such lost civilisations seems thin, and their existence is generally dismissed by the academic community. However, is it plausible to suggest, more generally, that civilisations may have risen and fallen before the beginning of the historical record?

The finding that Neanderthals interbred with modern humans, published in 2010, must mean that we are the same species. In fact, the ability of two organisms to breed and produce fertile offspring is the definition of a species. This pushes back the speciation of Homo sapiens to somewhere around 600,000 years ago.

We have been walking the Earth for over half a million years, and yet our historical knowledge goes back just 6,000 years at most. The prehistory of our species encompasses 99% of our past. The hypothetical existence of long lost civilisations lurking within that time frame is a tantalising possibility, and worthy of investigation.

The Rise of Civilisations

The last ice age ended around 12,000 years ago. Almost immediately after this, agriculture began to simultaneously develop in several locations around the globe. This led to more settled populations, which, in turn, led to the first cities and the emergence of civilisation.

In the Old World, civilisation developed in the Middle East (Mesopotamia), Ancient China and the Indian Subcontinent (the Indus Valley Civilisation). All of the subsequent Eurasian and north African civilisations can arguably trace their heritage back to these three ancestral cultures.

In the New World, civilisations arose in Mesoamerica (the Olmecs, Mayans, Aztecs, etc.) and South America (Norte Chico, the Incas, etc.). The great significance of these cultures is that they arose completely independently from all similar developments in Eurasia. This implies that civilisation was not just a fluke - humans will likely develop civilisation wherever conditions allow them to do so.

Given that within the 1% of human history that we are aware of, civilisation has developed in five separate locations, why should we not assume that there have been hundreds of lost civilisations in the prehistoric past?

Lost Civilisations - Possible Objections

One limiting factor is the Earth's cycle of ice ages. Within an ice age, there are glacial and interglacial periods. Agriculture is known to have only developed with the beginning of the current interglacial period, 12,000 years ago.

However, within our 600,000 year time frame, there have been a number of other interglacial periods: the Günz-Mindel interglacial (620 to 455 kya), the Mindel-Riss interglacial (380 to 200 kya) and the Riss-Würm interglacial (130 to 110 kya).

Given that agricultural development began as soon as the current interglacial period began, it seems plausible to suggest that similar bursts of agricultural development occurred with the beginnings of these prior three phases. In fact, the intervening glacial periods seem like a good explanation as to why no records of any prehistoric civilisations would have survived to the present day.

Another point to take into consideration concerns human migration patterns. Modern humans are only thought to have left Africa around 60,000 years ago. However, the ancestors of the Neanderthals are thought to have left Africa around 600,000 years ago. If we are the same species, then this dates the first Homo sapien exodus from Africa to the beginning of our prehistoric time frame.

Archaeology

Another objection comes from archaeology. Behavioural modernity is often associated with a leap in technological innovation which occurred around 50,000 years ago. This marks the boundary between the Middle Stone Age and the Later Stone Age.

In the Middle Stone Age, tools were simplistic, and had barely changed for hundreds of thousands of years. However, from 50 kya onwards, there was a rapid increase in the diversity and complexity of the human tool kit. This would suggest that, prior to this time, humans lacked the skills necessary to develop agriculture and, subsequently, civilisation.

However, this assumption is based on archaeological findings. Prior to the European discovery of the Americas, many of the indigenous tribes who lived in the areas surrounding the Meso- and South American civilisations were using relatively primitive stone age tool kits (although admittedly still significantly more modern than Middle Stone Age implements). At the very least, this demonstrates that civilisations can develop in the midst of technologically primitive cultures.

In addition, I suggest that there are reasons to suppose that little archaeological remains would exist of any lost prehistoric civilisations even if they had developed more complex technology.

Fallen Civilisations - What Would Remain?

Bob Holmes, a writer for New Scientist magazine, has speculated as to what would happen to our modern civilisation if all human beings were suddenly wiped off the face of the planet by some mysterious, hypothetical disaster.

Holmes states that modern buildings are engineered to last around 60 years, while bridges and dams are respectively built to last 120 and 250 years. Although ruins may remains for hundreds of years, many structures would vanish remarkably quickly. In addition, Brad Stelfox, a land-use ecologist in Northern Canada, estimates that 80% of urban areas in that region would be enclosed by forest within 50 years without human intervention.

Atmospheric carbon dioxide levels would be reduced to 15% of current levels within a thousand years, and return to pre-industrial levels within 20,000 years. After 50,000 years, most glass and plastics would have degraded. Following this, the only remains of our worldwide, post-industrial civilisation would be a burst of radio waves spreading outwards from Earth across the universe. All archaeological artefacts on the planet itself would long since have disappeared.

Given this, it seems unreasonable that we should expect to find any archaeological remains of any civilisation which may have existed prior to the beginning of the last glacial period, 110,000 years ago.

Conclusions

There is an important distinction between civilisation and industrial civilisation. Although civilisation itself is known to have arisen in multiple places (and arisen quickly, once conditions were right), industrialisation is only known to have occurred once. Equally, many claims of long lost civilisations are blatantly spurious.

However, our historical knowledge has been drastically changed by new findings numerous times in the past. The Indus Valley Civilisation was unknown of until the 1840s. The discovery of the Antikythera mechanism in the early twentieth century revealed that humans had been creating clockwork mechanisms around 1.5 thousand years earlier than previously thought. Göbekli Tepe, discovered in the 1990s, revealed that hunter-gatherer peoples had been constructing large stone temple complexes before the advent of agriculture and civilisation itself.

Given the time that the human race has spent on the planet, how limited our historical knowledge is, and how quickly we have developed agriculture and settled populations where able, it seems difficult to imagine that there have not been at least a handful of - and perhaps innumerable - lost civilisations in our prehistoric past.




Copyright © Dan Haycock 2011. For similar articles and information about Dan's forthcoming book, visit http://www.DanHaycock.co.uk

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