Teaching Evolution by Natural Selection

Capture chameleon

Here are some resources and activities for teaching evolution by natural selection at Key Stage 3 and Key Stage 4.

Bird beaks

This is a fun activity for demonstrating adaptive radiation in birds, as observed in finches by Charles Darwin during his famous expedition. Materials and procedure are detailed here but I use forceps, clothes pegs, chopsticks and toothpicks as beaks and red kidney beans, mung beans, raisins and rice for the four food types.

Peppered moth hunt

This exercise simulates how predators locate prey in different environments and is perfect for highlighting the fate of the infamous peppered moth.

You will need:

  • sheet of white paper
  • newspaper
  • forceps
  • stopwatch
  • 30 newspaper circles (made with hole punch)
  • 30 white circles (made with hole punch)

Steps:

  • Students work in pairs
  • Place a sheet of white paper on the table. One student should spread 30 white circles (‘pale peppered moths’) and 30 newspaper circles (dark peppered moths’) over the surface while the other student (‘the predatory bird’) is not looking.
  • The ‘predatory peppered moth’ then uses the forceps to pick up as many circles as he or she can in 15 seconds. This corresponds to the predator capturing and eating the moths.
  • Repeat the trial with white circles on a newspaper background, newspaper circles on a white background, and newspaper circles on a newspaper background. Record the data in a table and then ask the students to consider the following questions:
    • What type of tree surface is represented by the newspaper?
    • Which moth colouration is the best adaptation for a polluted background? How do you know?
    • Following the first trial, what has happened to the frequency of the allele for ‘pale’ colouration?
    • Moths which survive i.e. are not eaten by the predatory birds can pass on their alleles when they reproduce. How does the simulation model natural selection?

Giraffe stretch

This is a very quick and simple demonstration of variation and survival of the fittest. Before the lesson, I stick some paper leaves at the very top of the door frame. I then ask a small number of students (of different heights) to come and see who can reach the leaves (you may wish to remind them that giraffes can not jump or stand on chairs!).

plant

Phet simulation

For slightly older students Phet have an excellent interactive simulation of natural selection.

Capture phet

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