1. (i) Name, and describe, one feature characteristic of these, and all cephalopods (2)
(ii) Devise a simple key which would enable you to distinguish between the four cephalopods shown (3)

2. ZONE FOSSILS (F3 KI 2d) A fossil that can
tell you the time zone of when it lived
Because the fossil is restricted in time
can assign a precise date to the rock
We can use this to link rocks together and put together a history of the rocks (stratigraphic correlation)

3. ZONE FOSSILS
What makes a good one?
COSMOPOLITAN – Worldwide distribution – mode of life in shallow waters/free floating
EASILY PRESERVED – hard parts
EASILY IDENTIFIED – eg. Suture lines
PLENTIFUL – lots of them
SMALL SIZE – whole thing
FACIES INDEPENDENT – not tied to one rock type
RAPID EVOLUTIONARY CHANGE – so that an exact geological time period can be identified

4. RAPID EVOLUTIONARY CHANGE
I.D.A.T.E.
Identifiable
Distribution
Abundance
Time Period
Evolution
RAPID EVOLUTIONARY CHANGE

5. CEPHALOPODS (Ammonites) F3 KI 2d

6. So how do cephalopods fit into being a good zone fossil?

7. modern

8. Life scenes! Use of uniformitarianism to give mode of life Fossils are WIDESPREAD and can be FACIES INDEPENDENT

9. Rapid evolutionary change - Suture line

10. Straight shell, orthocone

12. Goniatite (earliest age range, oldest Upper Palaeozoic)

13. Ceratite (middle age range, Triassic)

14. Ammonites (youngest, most recent age range, Jurassic)

15. Ammonite (youngest age range)

16. Ammonites

17. So how can you make this memorable?
Any “words”?
Pictures?

19. Using ALL resources ….. Make a poster for cephalopods to revise
Suture line evolution …
Use internet, fossil diagram pack, OCR book page 262
Use the “REAL” plastercast to accurately DRAW the suture lines
HOW will you be able to remember the time zones? Mnemonics or memorable things?
CRITICAL EVALUATION: how well do cephalopods meet the “zone fossil” criteria?

21. Easily preserved?
Yes
Hard parts easily preserved

22. Easily identified? Yes Easy to tell species apart by suture line
Fabulous pictures of the amazing detail of preservations seen in these pictures!

23. Are cephalopods good zone fossils?
Wide and plentiful distribution
Easily preserved
Rapid evolutionary change
Facies independence
Easily identified

24. Zone fossil characteristics
Wide and plentiful distribution
Achieved by being free floating/swimming
Easily preserved
What is the creature made of? Will it preserve?
Rapid evolutionary change
Facies independence
Because it can travel across the globe – it can fall into any rock when it dies
Easily identified

25. RAPID EVOLUTIONARY CHANGE
I.D.A.T.E.
Identifiable
Distribution
Abundance
Time Period
Evolution
RAPID EVOLUTIONARY CHANGE

26. The largest Ammonite in the world?
Parapuzosia seppenradensis is Late Cretaceous in age and measures 1.95 metres in diameter. The end chamber is incomplete and probably would have had a diameter of 2.55 metres! Found in Germany in 1895.

27. Nautilus Sauceboats in Sterling Silver
Ammonite lamp posts in Lyme Regis

28. Pictures from….