1. Evidence of Evolution:
The Fossil Record

2. The Fossil Record
Fossils are the preserved remains of
prehistoric organisms.
Paleontology is the study of fossils.

3. The Fossil Record

4. The Fossil Record
Layers of sedimentary rock contain fossils.
New layers cover older ones, creating a record
over time.
When fossils are arrayed in the order of their
age, a progressive series of changes are seen.
The younger fossils are more similar to
existing species than older ones.

5. The Fossil Record

6. The Fossil Record
Fossils may be used to determine
information about species:
Size
Weight
Age
Location
Migration
Cause of extinction
Diet
Common origins

7. The Fossil Record
The Fossil record is incomplete and has many gaps.
Reasons:
Species with delicate bodies don’t fossilize.
Species may not have lived in conditions that
allow it to fossilize.
Fossils haven't been found.

8. Transitional Fossils
A transitional fossil is one that represents
characteristics between groups of organisms.
(the missing link)
It provides a link between past and present
species.

9. Transitional Fossils

10. Transitional Fossils
Archaeopteryx

11. Transitional Fossils
?

12. Transitional Fossils: Tiktaalik
Assumption:
Land vertebrates evolved from lobed-finned fish
Observations:
The first fossils of lobe-finned fish: 390 MYA.
The earliest fossils of land vertebrates: 360 MYA.
Prediction:
The transition to land occurred 390 – 360 MYA.

13. Transitional Fossils
Shrubin discovers Fishapod!
Four limbs with webbed fins
and sturdy wrist bones
Neck and shoulders
Thick ribs
Flattened skull

14. Transitional Fossils
Tiktaalik

15. Transitional Fossils

16. How is the Fossil Record
Evidence of Evolution?