The eternal winter had arrived. Snow covered everything and created a blindingly white world. Ice encased plants and animals. Frozen monuments, a reminder of a dead world.
Humans had been gone for centuries now. Their greed, their destruction of resources, their destruction of nature itself had caused a global collapse. A nuclear war had triggered a series of unexpected volcano eruptions and the ash had blackened the sky.
Sunlight was rare these days and usually only consisted of a few isolated rays before the dark clouds of ash drowned it out again. Without sunlight and without humanity’s industry to heat the atmosphere, the earth had cooled and frozen over.
Most animals had died alongside the humans, they hadn’t been able to tolerate the freezing temperatures. Most animals, but not all.
A handful of fish, insects, frogs, bacteria and, of course, the all famous water bear had been able to survive. At least for a while.
The secret to surviving this kind of temperatures had been known to nature for quite some time. Water needed to be prevented from forming ice crystals, as those would disrupt cell walls and effectively shred the organism. Many species invented their own antifreeze, usually some kind of proteins. They flooded their system with it and thus prevented their own death.
But for most animals, that was not a permanent solution. The frogs were frozen solid for some weeks but then, they couldn’t keep producing their antifreeze and died.
The fish, being adapted to the arctic waters, lasted a little bit longer. But they soon ran out of food, when the plants died because of the missing sunlight.
The thousands of insects that had used their survival techniques usually applied in winter had to realize that they weren’t adapted to a winter that lasted this long. Most of them never woke up
The tardigrades, the tiny water bears, known for being able to survive everything, completely dehydrated themselves to prevent ice from destroying their bodies. They fell into an eternal slumber, prepared to awake again when the weather would be warmer.
They were still sleeping.
Deep, very deep in the oceans, huddled around underwater volcanos, were the last survivors of the apocalypse. The earth’s core itself kept them warm. Tiny organisms, most of them were extremophilic bacteria. They were the last life left on earth.
And they were waiting. Waiting for the conditions to become better. Waiting for the circumstances that would lead to them re-populating the earth.
It might take billions of years, but they were patient. After all, they would become the next dominant species on earth.
Sources:
Animal ice-binding (antifreeze) proteins and glycolipids
When Built-In Antifreeze Beats a Winter Coat
When Your Veins fill with Ice
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