The Law of Doomsday Evolution

The birth of life on a planet takes hundreds of millions of years, but its destruction may only take a few years. A meteor shower brought Earth's creatures into light-speed evolution, but the ensuing insect tide plunged all humans into fear, and humans fell from the top of the food chain in the shortest possible time. Natural selection, survival of the fittest... Under the claws of extraterrestrial creatures, no one can escape. Only by constantly evolving in the face of adversity can one return to the top!