The Fossil Record

1
The Fossil Record

• pp. 279 - 281

2
Nature of Fossils

• Fossils are merely a trace of a long-dead
  organism. Some traces can be largely intact
  while others can be just imprints (aka molds).
• Most fossils are found in sedimentary rock

3
Fossils and Scientists

• The first scientist to study fossils was Robert
  Hooke. He studied petrified wood and stated that
  fossils are remnants of plants and animals.

4
Fossils and Scientists

• Nicolaus Steno shared Hookes view and proposed
  the law of superposition.
• This law states that successive layers of rock or
  soil were deposited on top of another by wind or
  water.

5
Law of Superposition

• According to Steno, the lowest stratum (layer) is
  the oldest while the top stratum is the most
  recent.

6
A Fossils Age

• Using Stenos law, the relative age of a fossil
  could be determined by saying a fossil is younger
  or older than another according to where it was
  found.

7
A Fossils Age

• The absolute age (age in years) could be
  determined by how much sediment was deposited
  onto of the fossil.

8
Fossil Location

• Fossils have been found in the same area where
  similar living organisms have arose and made
  their home.Ex. Armadillo/Glyptodont home is in
  N. S. America