Fantastic Fossils

 In year Three, we learnt about fantastic fossils! We discussed how we know dinosaurs existed through what palaeontologists have learnt from looking at fossils. We talked about body fossils and the three types there are:

• Mould fossils form when all the parts (including the bones) have decayed and all that is left is the mould of the animal. Cast fossils form from mould fossils as the mould fossil is filled up with sediment – so it is not made up of the original matter of the animal or plant.
  
  
• Replacement fossils form when water dissolves the original hard matter of the bones and replaces them with mineral matter – this is what we think of when we discuss dinosaur fossils. They still look like the original bones but are not made up of the same matter.

• Whole body fossils form when the original body has been preserved – for example a woolly mammoth in ice or a mosquito in amber. 

Using plasticine and Plaster of Paris, we had a go at creating our own fossils! We used plasticine to represent the sedimentary rock which our dinosaurs had died on top of. We then pressed our dinosaurs into the rock to show how the sediment then builds up over time. After that, we removed our dinosaurs to represent how the bodies would have decayed. Next, we filled the imprint which was left behind with plaster of Paris - this was to show the process where water dissolves the bones and fills the space left behind with minerals.  We then put our palaeontology hats on and removed the plasticine to reveal our fossils!

These photos really capture the WOW moment!