"Acid Test: It's all go on our dynamic planet"
By Matt Ridley
Copyright 1999 The Daily Telegraph (London)
Monday, January 18, 1999

THE NEWS is suddenly full of ancient geography. Beachy Head collapses as the English Channel is nudged wider at a rate measured in miles per millennium. The colonisation of the Pacific by people has been chronicled in the genes of a lizard and it turns out to have happened as fast as an "express train" - that is, it took only "a few centuries". The land bridge across the Bering Strait has been redated by a few thousand years. The Andaman islanders have been proved to be ancient African emigrants marooned off the coast of Asia when the sea rose 40,000 years ago. All this happened (or, rather, hit the news) last week.

Yet even these reminders of the immensity of time - can you even imagine 40 millennia? - are dwarfed by true geological time. The newly pristine white cliffs of Beachy Head took many thousands of millennia to form from the slow drizzle of plankton on to the sea bed of an ancient ocean. The whole history of civilisation is, in the history of our species, but a fingernail clipping on the end of an arm; but compared with the history of life on earth, it is a fingernail clipping on the end of an airport runway.

I have often wondered how long traces of us would remain if all people went extinct tomorrow. Suppose it took another 100 million years before another intelligent species stalked the earth: would it even know that it had once been preceded? The continents would have moved so that Antarctica was tropical and Australia in the northern hemisphere. Most of the seabed would have been melted and reforged. Mountains would have been flattened, deserts greened and rainforests become deserts. Our cities would have crumbled, eroded, washed out to sea and slowly vaporised.

WOULD any trace remain? Even the gigantic crater that was carved into the rocks of Mexico (as it then wasn't) by the meteorite that killed the dinosaurs 65 million years ago has only recently been discerned with the help of sophisticated instruments. If the same happened to us, would anything endure? Sure, there would be fossils for the diligent to find: thin etchings in the rock of a plastic sandal left on a beach that had since become sandstone, or dim outlines of discarded televisions in shale formed from the mud of a long-solidified pond. Perhaps even, if the diligent future being were lucky, a fossil of the creature that made them. But that seems improbable, for we bury our dead in a place where fossilisation is unlikely: organic soil.

Yet there is a difference between slow and gradual. Earthquakes are the means by which continents move very slowly, yet they are by definition sudden and violent. The widening of the English channel is in our terms happening slowly, but, as we saw this week, it goes in such lurches that it could squash you. When the Mediterranean sea dried up five million years ago, it was refilled quite suddenly over the Gibraltar isthmus by a marine cataract that had the volume of a thousand Niagaras. Something similar may have happened at the Bosporus 7,000 years ago, giving rise to the legend of Noah. Over 3,000 years the Columbia river in the western United States was more than 40 times the victim of floods from an ice dam - each one of which had more water in it than 60 Amazons.

Beachy Head reminds us that we live on a dynamic planet. Even apparently static things are actually moving; nothing stays the same for ever. The environmental movement likes to play on our failure to appreciate this point. It demands that we take responsibility for climate change, sea level, the retreat of ice caps, even though all of these are partly - perhaps still chiefly - natural processes. It fixes oak forest as the "natural" ecosystem of Britain, even though the oak was a newcomer that had usurped the place of pine, birch and alder and would in turn have been replaced by sycamore if the Channel had not intervened. A few loony greens have even tried to pin the blame for Beachy Head's collapse on human action. Why do we so dislike change?