Specific workshop information
Planning and preparation
- Lego bricks or similar
- Aluminum Foil
- Plaster of Paris
- Burlap (natural hessian jute roll), gauze or any loosely woven natural material cut into 5-7 cm wide and 30-40cm long strips
- A bucket or plastic washing-up bowl is needed for holding plaster mixture (be sure the students would be able to get their hands in the container)
- Large container for mixing plaster(optional)
- A large spoon or many smaller spoons or wooden tongue depressors
A good task to complete before the demonstration event:
- Using the Lego, have students construct a long rod-like bone (50-100 cm). A great bone to base your Lego model could be a femur (left, thigh bone) or maybe a humerus (right, upper arm bone) from an hadrosaur dinosaur (see image below). This will be their dinosaur bone.
- Ask the students:
- What would happen if they were to drop it?
- How they would be able to take it home from school without it breaking?
- Tell the students to imagine their Lego bone is from a Tyrannosaurus or Edmontosaurus that is 66 million years old and that it is just one bone from over 200 they found at a dig site in the middle of nowhere. They now need to figure out how to move the fossils over 4,400 miles from the Badlands of Montana in the United States to the UK…without a single new fracture appearing in their previous fossil.
- What are the different modes of transportation they would need to use to move several tonnes of dinosaur bone from the US to the UK?
- How would they prevent the bones from being broken when they are being moved and bounced around on rough roads, rolled around by large waves in a ships hold, or rough air turbulence in air-freight?
- It is also good to discuss the dinosaurs carbon-footprint, as moving these objects involves the burning of hydrocarbons (fossil-fuel)!
- You can spend as much time on these inquiry-based questions as needed. You can even let them build another dinosaur bone in a different shape for the next set of tasks.
During the session:
- Students will be introduced to some of the researchers (Prof. Phil Manning and Dr. Victoria Egerton) and watch recent footage of the team excavating and recovering a huge dinosaur skull (~1.3 metres long) from the Hell Creek Formation (Montana, USA) being safely moved around the world for study. The fossilized hadrosaur dinosaur skull was discovered just below the famous KPg (Cretaceous/Palaeogene) boundary that marks the moment when a vast 10km wide meteorite smashed into what is now the Yucatan Peninsula (Mexico) causing a chain of events that led to the planets last Mass-Extinction event (when around 75% of species become extinct).
NOTE: Dependent on class size and the needs of the students, teachers may wish to consider asking for additional adult support to run a few demo’s around the room so students can see in detail or help supervise the students in small groups so they can have a go themselves.
- We will now proceed to learn how palaeontologists make and use field jackets to move delicate fossils. Field jackets are typically made of burlap dipped in plaster and left to harden. This creates a hard shell to protect fossils and to prevent them from shifting around while they are being moved.
- Take your Lego bone and wrap it tightly in aluminium foil. Be sure to cover it completely so that you don’t see any of the Lego bricks. You can use a 1 inch paintbrush to help gently push the tin-foil into every knock and cranny that the Lego bone has. If the foil breaks, you just add another piece of foil over the break, until the whole ‘bone’ is covered.
- This is a separating barrier that will keep the plaster from getting on the ‘bone.’ Palaeontologists either use aluminium foil, wet paper towels, or even toilet paper if there is nothing else available. Using a separating layer keeps the bones clean and means less work back in the preparation lab.
- Now you will need to mix your plaster. Follow the instructions on the Plaster of Paris container to create the wet plaster mixture necessary to make the jacket (consistency of single-double cream is ideal!). It is sometimes worth making a small test batch to see how quickly the plaster sets, as this will give you the time available to work the plaster onto the field jacket (before it sets too hard to work). You may want to make a single batch large enough for your entire class and then pour it into individual containers for the students. Alternatively, you can have pre-measured amounts of dry plaster and water ready for the students to mix it at their tables.
- Once the plaster is thoroughly mixed, dip and completely soak your burlap bandage into the mixture to coat it. You don’t want too much plaster as it will become very messy, so drawing the burlap between two fingers will remove excess plaster mix and made the ‘bandage’ easier to handle (for those who don’t want to use burlap, you can use ready-made bandages that just need to be dipped in water before wrapping around the bone).
- Carefully wrap the plaster bandage around the aluminium covered ‘bone.’ Be sure to form it to the shape of the bone. With each plaster bandage you can start to criss-cross the layers to add strength to the final jacket.
- Continue with steps 4 and 5 until you have at least 2-3 layers worth of plaster covering the ‘bone.’ Keep in mind that plaster hardens quickly, so once the mixture is made, keep an eye on the plaster in your container.
- Let the field jacket harden.
- You have now created your very first field jacket! You would now be able to safely move your dinosaur bone around your classroom without having to worry about it being broken.
- Note for teachers: To open the jacket and get to the Legos, you should be able to use scissors or a utility knife to cut open the jacket. This is not recommended for students!