Life Science · Evolution & Variation
Natural Selection: Why Some Traits Become More Common
Investigate how inherited variation can affect the chance of surviving and reproducing in a particular environment, using fictional population evidence rather than an individual choosing to change.

Lesson plan
Natural Selection: Why Some Traits Become More Common
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Lesson overview
What students will learn
- Interpret fictional population data as evidence that inherited trait variations may change an individual's chance of surviving and reproducing in a particular environment.
- Explain how selection acts on existing inherited variation, not purposeful trait changes by individuals.
Key science ideas
- Individuals of the same species can differ in inherited traits; variation exists before the environment favors any one trait.
- In a particular habitat, one inherited trait may increase the probability of surviving long enough to reproduce.
- Offspring may inherit the trait; over several generations its frequency in the population can change.
Lesson at a glance
- Grade 6
- 55 min
- ~12 min prep
- MS-LS4-4
- 4 materials
What’s included
- Lesson Plan
- Investigation
- Teacher Slides
- Printable Worksheet
- Teacher Answer Key
- Interactive Activity
- Vocabulary