Biological Timescale

Objectives

• Explain the biological timescale using a model.

Materials

• Per Class or Group:
  100 metre measuring tape (as used in track and field sports)
  flagging tape
  masking tape
  marker

Key Questions

• What type of organism has been on Earth the longest?
• The dinosaurs died out about 65 million years ago. How many more years was it until the first human ancestor appeared?
• What type of animals were the first animals with backbones?

What To Do

Use the analogy that 4.5 billion years is equal to 100 metres.

 

 

1. Unroll the tape in an outdoor space.
2. Have students locate the following times on the tape measure.

 

 

 

 

 

 

1. Have students write each event name and time on a piece of flagging tape.
2. Using masking tape, have students attach each piece of flagging tape to its corresponding position on the 100 metre tape.
3. Have students examine the completed time scale.

Extensions

• For a more challenging activity, have students calculate the scaled distances themselves!