1. Fun Fossil Friday!

2. Fossils form when bones
are buried in sediments.
Minerals gradually replace
the bone, creating rocks
shaped like bones.

3. Layers of soil can be laid down by plants, wind,
surging water, or volcanic ash.

6. Forming sedimentary layers is a slow process.
Younger layers are on top.

7. Sediment layers go back
millions of years
Organisms change as we
look back in time

8. We don't see rabbits down
in the Paleozoic era,
or a Tyrannosaurus Rex up in
the Cenozoic era

9. The Fossil Layers

10. The fossil layers are the same on every continent, even Antarctica

11. Weathering can uncover fossils

17. 99.9% of all the species that have ever lived
are now extinct, like this one, a trilobite

18. Leaf Fossil

19. Fossil of extinct horse

20. T-Rex Fossil being excavated