Populations evolve, not individuals. 

Let's take a look at the Brightstorm video, Evolution of Populations. 

Natural selection can take one of three paths:

• Directional selection - favors phenotypes at one extreme
• Stabilizing selection - favors the intermediate phenotype
• Disruptive selection - favors both extreme phenotypes

To make sure you're understanding these three types of selection, watch the Teacher's Pet video, Types of Natural Selection.