3. What Was a Dinosaur?

Dinosaurs are not reptiles

Dinosaurs shared the same ancestors as crocodiles and other reptiles (archosaurs), but dinosaurs were quite different, they may have been closer to birds.

Dinosaurs had straight legs tucked underneath their bodies. Reptiles had a ‘spayed leg’ stance.

What are some other differences between dinosaurs and living reptiles?

Part 1 – Build model dinosaurs and reptiles.

For each animal you need:

• 2 cardboard cylinders (eg. toilet rolls)
• 8 x 15 cm lengths of stiff wire
• pliers, scissors, sticky tape

To build a dinosaur:

Bend the wires into legs for model animals.

Assemble the ‘animals’ as shown.

Which one looks most like a living reptile (eg. lizard, crocodile)?

Stand the ‘animals’ alongside each other.

Press down on their backs.

Which one supports your pressure the best?

Part 2 Make yourself into a splay-legged animal. See how fast you can move.

What you need:

• a friend
• a stopwatch
• 15 m to run

Make yourself into a SPLAY–LEGGED animal. Get into a push-up position with your hands and legs as far apart as you can. Ask you friend to time you over 15 metres.

• How fast can you move?
• Now make yourself into a STRAIGHT–LEGGED animal.

Now get into a squat position. Place your hands on the ground and place your knees under your hips.

• Can you crawl faster and further now?
• Which arrangement seems best for active animals?

Notes for teachers

This activity examines the skeletal differences between dinosaurs and living reptiles.

Encourage students to look in the library for books with drawings of dinosaur skeletons. Have them answer the following questions.

• What leg arrangement do scientists think dinosaurs had?
• Have scientists always thought dinosaurs looked like this?

Back to Terrorsaurus Resources

Back to in school activities