Natural Selection Graphs

stabilizing selection (example)

Birds usually laying 4 eggs because laying more or less is not good (more-starving, less-might die and then none left)

disruptive selection (example)

Birds with very large beaks can crack open a larger seeds. Birds with small beaks can eat insects easily. Medium beaks are not as helpful.

directional selection (definition)

Natural selection in which ONE EXTREME form of a trait is favored and becomes more common

stabilizing selection (definition)

Natural selection in which THE AVERAGE form of a trait is favored and becomes more common

disruptive selection (definition)

Natural selection that favors individuals with EITHER EXTREME form of a trait

directional selection (example)

When pollution made trees darker in an area, darker moths blended in best and survived more often. The population of moths began to be darker.