Fossils

4. Hard remains or traces of ancient organisms found in rock.
6. Kept safe from decay; protected over time.
8. A mark or impression left behind by an organism, such as a leaf or footprint.
10. Giant reptiles that lived millions of years ago and are now extinct.
12. A scientist who studies fossils.

1. Fossils often form over this many years.
2. Hard structures that form the skeleton of animals.
3. When a species has died out completely.
5. A type of rock made from layers of material compacted over time — fossils are usually found here.
7. What is left of an organism after it dies.
9. A type of fossil made when minerals fill in a mould and harden into shape.
11. The surname of a famous fossil hunter from Lyme Regis.