Post apocalypse, a small colony of pigs survive in a cramped, dank cave. They are losing more and more of their vision as the days wear on and will soon be completely blind. This is cause for despair, as their prey, the vicious termitorius, will run rampant with the pigs' extinction.
Pigs are dropping like flies! Some fall into crevices and some cannot find food as they go blind. The termitorius become more and more populous, as they undergo a process called overpopulation. The deadly insects multiply at an unsustainable rate, reproducing like rabbits because their natural predators are on the brink of extinction.
Over time, the organisms breed and some of them become different from each other because they each have different mutations through a process called variation. They change sizes, color, and in other unseeable genetic ways.
The last colony of pigs are extinct. The termitorius are the only group of life left on Earth. They are encountering obstacle, however, as the Earth's core warms to a nearly unbearable temperature. The termitorius species is in trouble. They are dying, and only have one way they can possibly survive...
There are only a few temitorius left. At this point, they are resorting to cannibalism and other forms of survival. The only way they can survive is to adapt to their sweltering environment.
Through a process called adaptation, some of the termitorius develop thicker, more breathable shells that allow them to survive the heat while also taking in more oxygen. Although only a few survive the harsh environment, they will reproduce and eventually most of the termitorius will have the same advantageous traits.