Steps Of Natural Selection: Natural Selection Sequencing

In the mid-1800s Charles Darwin (1809–1882) developed his theory of evolution based on natural selection. Natural selection means those organisms with traits (variations) that are best suited to the environment are more likely to survive and reproduce. In most populations, there are more organisms than can survive, and each organism is unique. For this reason, the environment selects the organisms that will be the survivors. In this activity you will arrange the principles of natural selection in the proper order.

Materials

Sheet of notebook paper; Scissors; Pencil

Activity

1. Copy and cut out the five steps of natural selection that follow. (They are not listed in any particular order.)
   • Organisms produce more offspring than can survive.
   • Over time offspring with helpful variations expand the population and can eventually become a separate species.
   • Differences or variations occur among individuals of a species.
   • Some variations are helpful, and individuals with helpful variations survive and reproduce.
   • Variations among parents are passed to offspring.
2. Arrange these steps in a logical sequence as Darwin might have done.

Follow-Up Questions

1. What was the sequence of your steps?
2. Could any of the steps be omitted? Why or why not?

Answers

1. The following sequence is correct:
   1. Difference or variations occur among individuals of a species.
   2. Some variations are helpful, and individuals with helpful variations survive and reproduce.
   3. Organisms produce more offspring that can survive.
   4. Over time offspring with helpful variations make more of a population and can become a separate species.
   5. Variations among parents are passed to offspring.
2. No. Answers will vary as to the reason all steps are essential.

Extension

Do some research and find a real-life event that illustrates the principles of natural selection. Match the steps of the event you researched to the principles you sequenced in this activity.