One trait among rabbits is running speed: there is variation in the population concerning this trait.

This is a heritable trait: fast rabbits tend to have fast offspring; slow rabbits tend to have slow offspring.

A slow-running rabbit is more likely to be eaten by a fox, and less likely to leave slow offspring.

Over time, the population evolves by natural selection: rabbits are fast.

Thus speed confers greater reproductive fitness for rabbits.

• Are there other traits that allow a slow-running rabbit to have reproductive success?
  • Some other possible traits: foraging ability, camouflage, breeding capacity