Originally posted by JohnnyCanuck
Originally posted by Fraank Fontaine
There was a recent BBC documentary following a scientific investigation. The documentary centred around the premise that if Man stopped to exist 'right now', how long would traces of our current civilisation last. Computers, buildings, cars, etc
The answer was surprising - around 400-500 years MAXIMUM! After this time, only the biggest of stone monuments would be around, and nothing of civilisation would be left.
Then how come we keep digging up artefacts that cover the whole range of human existence? Not to mention heritage landscapes, etc, etc. And most artefacts are...to some degree...diagnostic. Think about your statement, please.
Like they say "Love is fleeting, but stone tools are forever".
Exactly... 'stone' tools. Everything else, in all but the most exceptional of circumstances, is destroyed by natural processes. I am not talking about things deliberately preserved by being buried, or by chance of fate, being amazingly well preserved.
I am talking about houses, telegraph poles, reinforced concrete and the like. The documentary I was talking about was called 'Life After People', and was shown last year on the History Chanel. Details can be found here
In short:
75 Years - By now, most of the roughly 600 million automobiles in the world, even in the most forgiving of environments, will have rusted away to barely recognizable skeletal heaps. The tires will have deflated within a few years after people, but the synthetic rubber and plastic components will last for centuries.
100 years - The Brooklyn Bridge and the Golden Gate Bridge finally collapse when their rusted cables snap and can no longer support the weight of the road deck. Within a controlled environment of a preservation vault, materials such as paper and film can last 200 to 300 years, but once exposed to moisture and unregulated temperatures, they will have deteriorated away in half the time. In a humid environment, most books will have been eaten away by mold. Digital media such as CDs and DVDs will take longer to degrade, but ironically, they will not last nearly as long as the information once recorded by primitive cultures on clay tablets.
150 years - In major cities, the support columns of flooded subway tunnels fail, causing cave-ins and collapsing sections of the streets above. Vines have climbed up and into the gutted buildings where pools of water collect. Plants now grow throughout the floors, forming vertical ecosystems. Birds, rodents and snakes have moved in, followed by the descendants of house cats who find all they need to survive in one place. After generations of breeding with wolves, domestic dogs have returned to their pack hunting nature. Without the interference of man, the oceans recover from pollution and populations of sea life will have exploded. Seagulls, once dependent on human refuse for survival, would have a large die off decades ago, but the birds make a comeback once the fish populations return.
200 years - In the midst of the "Era of Collapses", many of man's greatest structures, such as the Eiffel Tower in Paris, the Tower Bridge in London and the Space Needle in Seattle, will have fallen. Once their iron structures succumb to corrosion, a strong wind would be enough to cause them to collapse. An example given in the show is the collapse of the neglected Kinzua Railway Viaduct in Pennsylvania in 2003. The collapse of the Willis Tower (formerly known as the Sears Tower) in Chicago and the Empire State Building in New York City will soon follow.
500 years - By now, most reinforced concrete structures will crumble away once the
iron rebar supports inside them succumb to moisture and the expansion of rust bursts them apart. Without humans to maintain them, it is believed that long standing ancient structures, like the Sphinx at Giza, will have eroded away within 500 to 1000 years.
1,000 years - Nature has re-established itself and nearly all evidence of modern civilization will have vanished. Most modern cities would be collapsed, become barely recognizable husks overgrown by a jungle of trees, waters, flowers and vegetation. New York City may look as it did when it was first explored by Henry Hudson in 1609.
10,000 years - By now, little evidence is left of mankind. Even our radio and television signals that were beamed into space, and once thought to traverse for hundreds of light years, will have faded to unrecognizable static at close to two light years and not even reach our closest stellar neighbor, Alpha Centauri. The Great Wall of China in Beijing will have aged like a mountain as it decays very slowly over the centuries. The Pyramids at Giza remains, but will have stood long enough to be swallowed up by the Sahara Desert's sands. Hoover Dam remains to be the last of the great collapses. Mount Rushmore in Rapid City will be one of the last symbols of man. Carved from granite, it will remain visible for millennia, possibly to be viewed by man's replacements, which may be chimpanzees if they evolve to take up the mantle of civilization.
