Populations and evolution

What you'll learn

1. 1

   Imagine a population of rabbits in a field. Some have brown fur, some have white fur. The environment changes — snow falls more often. Which rabbits survive better?

2. 2

   In a snowy environment, which rabbit is more likely to survive?

3. 3

   Drag the rabbits to the snowy field. Which ones blend in and survive?

4. 4

   Let's work through an example: A population of beetles has brown and green individuals. Birds eat the brown ones more. What happens?

5. 5

   Which of these is a key idea in evolution by natural selection?

6. 6

   Use the bar chart to see how a population changes over time. Start with 50% green beetles, 50% brown. After 5 generations, what happens?

7. 7

   What is the main cause of evolution by natural selection?