Visit Your Local PBS Station PBS Home PBS Home Programs A-Z TV Schedules Watch Video Donate Shop PBS Search PBS
Click to return to the Evolution Home Page
darwin change extinction survival sex humans religion
Online Lessons for Teachers: Learning Evolution

LESSON 4: Teacher Page

 How Does Evolution Work?

In the wild, species must cope with changing factors in their environment -- new predators, fewer available resources, more difficult access to mates, and variable weather. The interaction of all of these factors, coupled with the gradual nature of the changes that result, make evolution a complex subject to study. With these hands-on labs, students delve into realistic, yet simplified, models of the natural world. They learn how natural selection influences evolution.

Note: Breeding Bunnies could be used as part of a genetics unit. It shows how genetics provides insight into the mechanisms of evolution.

Activity 1: Breeding Bunnies

 This activity will take two class periods.
Image of a rabbit.

Students complete a hands-on lab simulation of natural selection. They learn how natural selection influences a breeding population of rabbits.

Learning Goals


Understand natural selection


Understand what genetics can tell us about the evolution of a population of organisms

Activity 2: Flashy Fish

 This activity will take two class periods.
Image of a fish.

Students will replicate a real experiment and examine the interplay between selection factors in a population of guppies.

Learning Goals


Understand how natural selection acts to influence particular traits in a population


Learn how different predators impact the same population in different ways

Additional Activities
Explore a range of mating behaviors and the concept of genetic drift.

View LESSON 4 Student Page

 Scientific Terms


Dominant Allele




Gene Frequency


Hardy-Weinberg Principle






Natural Selection


Recessive Allele


Sexual Selection

Assessment Rubric
Guidelines for assessing students' mastery of activity.

National Science Standards for LESSON 4

Icon with a clock, representing 45 minutes of class time.Time to Learn!

Each clock icon respresents approximately one
45-minute classroom session (not including homework).

Videos Web Activities Site Guide About the Project FAQ Glossary Site Map Feedback Help Shop