After reading many, many stories about the absolute horrors of the natural world, I have such a difficult time understanding a belief in a benevolent god. After all, it is trivially easy to imagine a universe with less suffering (but perhaps still enough hardship to drive inquisitive and motivational behaviors), so the presence of so much unnecessary horror in nature leads me to believe either (a) God is a sadist or (b) natural selection in the face of scare resources is what causes this pain.
One of my favorite (or, rather, terror-inducing) examples is the parasitic emerald wasp, which uses its paralyzing sting to turn a cockroach into a "zombie" so it can drag it by its antenna into a burrow, then lay eggs on the roach, and when the larvae hatch they proceed to eat the roach, but in a specific order so that the organs necessary for survival are eaten last. Queen Cersei from Game of Thrones couldn't come up with more nightmare-inducing torture.