Case study: Jelly Beans.
A box of jelly beans comes in all sorts of flavour. However, due to human taste and perferences, certain jelly beans which taste nicer than the others are at a selective disadvantage and may fall prey to the human being.
One of which is the red strawberry-flavoured species of jelly bean. Because of natural selection, nicer tasting jelly beans like this are selected against, hence decreasing their population size. This puts the other jelly beans at a selective advantage as they are able to avoid predation.
Fig 1: Apparent lack of red-coloured species of jelly bean in the jelly bean population.
Even though these other jelly beans are able to survive, they cannot reproduce and pass on their distasteful genes down to the next generation because they are a hybrid cross between jellies and beans, thus rendering them sterile.
