Event One:
A butterfly - possibly a cabbage white, or similar variety - spreads itself across a leaf in New York's Central Park.  It stretches lazily in the warm sunshine and contentedly flaps its wings.  This motion generates a small current of air, barely perceptible, but sufficient enough to divert the course of an airborne spore.   The spore lands beside a pathway and begins to germinate.

Event Two:
One year later and the spore has blossomed into a thriving example of a Patagonian trailing creeper.  It spreads its tangled strands out across the adjacent path. An early-morning runner fails to notice it as he is jogging along. He becomes entangled and falls, dropping his doughnuts and fracturing his shin.

Event Three:
At a nearby hospital, the runner is waiting for the results of his X-ray.   He decides that something should be done to prevent others from having similar accidents.  As  luck would have it, he happens to work for the Mayor's office, where he has some influence.  At his request, a program of defoliation is begun to eradicate all traces of Patagonian trailing creeper from Central Park.

Event Four:
All traces of the troublesome creeper have now been cleared.  The creeper was also home to a species of beetle and these too are wiped out - starving the local population of hammerhead gannets, who feed on them.  The gannets are forced to find other sources of food and for a while they make a nuisance of themselves by raiding trashcans, harassing hot dog sellers and occasionally carrying off small pets.   However, they cannot adapt and they soon begin to die off.

Event Five:
The hammerhead gannet is a remarkable bird in that it usually expires in the air - rather than on the ground, up a tree or inside a cat like most birds.  New York suddenly finds itself plagued by falling birds as the dead gannets plummet from the skies, mid-flap. As their name suggests, the hammerhead gannet has a head shaped like a small mallet and the descending birds do considerable damage to roads, buildings and the occasional unlucky bystander.  Sales of crash helmets rise steeply.

Event Six: 
While some crash helmets are made from specially hardened synthetic composites, they are no match for the traditional variety, fashioned from the shell of the Polynesian backflip tortoise.  The backflip tortoise is so called because of its fondness for acrobatics.  Sadly, despite hours of practice, most backflip tortoises make poor gymnasts, and so they have developed hardened shells to protect them from injury.  Because of the increase in demand for crash helmets, their numbers soon begin to decline.

Event Seven:
The shells of backflip tortoises are also used to make lobster pots.   However, with fewer tortoises available, lobster fishermen have to rely on other materials.  These new pots are just not up to the job.  The lobsters themselves are certainly not impressed and simply gather around them, pointing and laughing contemptuously.

Event Eight: 
The lobster population swells out of control.  They become rowdy and boisterous - holding underwater raves, getting high on seaweed and playing Beach Boys records until four o-clock in the morning.  The octopuses that live next door start to get really hacked off with it.  Octopuses are usually quiet and genial creatures, who are at their happiest when left alone to do word puzzles.  But on this occasion they realise that something has to be done, and so they decide to stage a sit-in.

Event Nine:
Octopuses from all over the world gather in the Atlantic Ocean to protest.   Their numbers are so great that they disrupt shipping and cut off the Gulf Stream, the current that supplies warm water to the North Atlantic.

Event Ten:
With the Gulf Stream disrupted, the world begins to freeze.  The arctic ice begins to encroach on Canada, Europe and Northern Asia.  Before long the tundra has enveloped Manchester, and the polar bears move in and turn it into a winter resort.

Event Eleven:
As luck would have it, a syndicate of four million penguins from Antarctica have won a fortune on the lottery and, hearing that the skiing in Manchester is particularly good at this time of year, they decide to blow all their winnings on a vacation.  As penguins can't fly, they invest in rocket packs and set off en masse.

Event Twelve
Passing through Indian airspace, the captain of a Korean airliner is astounded to see four million penguins wearing rocket packs approaching him, directly on his flight path.  The penguins are equally surprised and swerve abruptly to miss the plane.  Unfortunately, they fly smack into Mount Everest, knocking the top off.   The shock wave travels around the world, triggering earthquakes in - amongst other places - California, Japan and China.

Event One:
A massive earthquake hits rural China. Although disruption to the human population is minimal, it displaces a large population of moles, who leave their homeland and set off in search of pastures new.

Event Two:
The moles arrive in Indonesia and make a new home for themselves.  They flourish and before long they take over the whole country, turning it into a giant golf course (moles are keen golfers, although they are terrible cheats - they dig their own holes).  The Indonesian economy soars as the country begins to attract the idle rich from all around the world.

Event Three:
Success has a price, and the Indian Ocean soon starts to fill up with golf balls.  This drastically increases the erosion on the coast of India.   Eventually, a huge chunk of the country breaks off and floats out to sea.

Event Four:
This broken off chunk of India - now known as Little India - spends several years floating around the world, enjoying some splendid scenery and excellent whether.  It becomes a tax haven for teen pop stars.

Event Five: 
Little India's world tour comes to an end when it becomes wedged up against Florida.  The teen pop stars decide to buy the state and turn it into a giant swimming pool.  A few of the locals manage to find work as pool boys, waiters or bartenders, but the rest have to leave and go in search of work elsewhere.

Event Six:
The teen pop star invasion of Florida has other consequences.  In addition to driving out much of the human population, it also forces out many of the alligators.  They are forced to hit the road and end up travelling the length and breadth of America's highways, performing juggling tricks in return for handouts.

Event Seven:
Some of the alligators band together and form a travelling circus.  They go from town to town, performing for the locals - fire eating, tightrope walking, eating clowns and such like.  The highlight of the show is Snaps McDougal and his amazing escapology act.

Event Eight:
One night during a show in Maine, Snaps McDougal is spotted by a promoter who offers him a six month residency in Vegas.  Snaps agrees and he becomes a big hit.  His fame rapidly spreads across the country.

Event Nine:
Snaps McDougal is now a household name, and his celebrity does much to raise the profile of alligators everywhere.  Talent scouts and agencies start to realise that 'the next big thing' is likely to be about nine foot long and covered in green scales.  Producers and directors start searching for alligators to star in their latest movies, and more and more of the animals are offered headlining roles on TV and in Broadway productions.  And its not just alligators - crocodiles, monitor lizards and even snakes all experience an upturn in their fortunes.  A pair of Polynesian backflip tortoises go down a storm in a remake of Trapeze.

Event Ten:
Reptiles are now dominating the entertainment industry to such an extent that human performers find it almost impossible to get work. Demonstrations all over the country culminate in a protest march through the streets of New York. Actors, dancers, singers, mime artists and speciality acts bring traffic to a standstill as they wave placards, chant slogans, enact sketches and perform elaborately choreographed musical numbers whilst leaping about on car roofs.

Event Eleven:
Realising that there is no way that she is going to get to her office on time, a young girl leaves her cab and decides to take a shortcut through Central Park.  It's a warm day and the sun is out.  There had been a slight drizzle earlier - it had passed quickly but the ground is still damp.   As she walks along her arm brushes a nearby bush, shaking a little shower of sparkling raindrops from the wet leaves.  She moves on without another thought.

Event Twelve:
Sheltering beneath the bush is a butterfly - possibly a cabbage white, or similar variety.  As the leaves above are disturbed, raindrops smash to the ground around it, covering the insect in diamond shards of moisture.  It cautiously inches back, moving deeper under cover. And then, to dry itself, it very gently flaps its wings.