Fossils
The traces or ________________________ of an organism that lived long ago.
Fossilized Organisms
Fossils in Rocks
1)the organism ___________________ and becomes buried in
_______________________
2)most fossils are found in __________________________
Fossils in Amber
The organism gets caught in _________________________________.
Frozen Fossils
1)Organisms are _____________________ because of low temperatures.
2)_____________________
Fossils in Asphalt
1)Pools of thick, sticky _________________________ trap organisms.
2)La Brea tar pits in ________________________
Petrification
1)_________________________ fill or replace the organism’s tissues.
2)________________________
Other Types of Fossils
Trace Fossils
1)Any evidence of animal _______________________________
2)footprints, __________________, _____________________, coprolite
(fossilized animal _______________)
Molds and Casts 1)mold: the _____________________________ left of the organism
2)cast: when sediment ______________ the impression left by the organism
Using Fossils in Interpret the Past
The Information in the 1)fossil record: record of all the _________________ that have been
Fossil Record
found
2)It is _____________________ because most things that died didn’t
become a fossil. Fossils are _____________.
A History of
1)Fossils can show changes in the _____________________.
Environmental
2)Antarctica was _________________ in the past because there is
Changes
evidence that _________________ and water organisms once lived
there.
A History of Changing 1)fossils show ___________________ in organisms over time
Organisms
Dating the Fossil Record
Using Fossils to Date
1)__________________ fossils: fossils of organisms that lived during
Rocks
_____________________ periods of time
2)these fossils must be found all over the __________________ and
must be easy to __________________________
3)they are used to find the __________________ of the rock layer
Trilobites as Index
A rock layer with a Phacops __________________ fossils shows the
Fossils
layer is _______________ million years old.
Ammonites as Index
A rock layer with a Tropite ____________________ fossils shows the
Fossils
layer is _____________ million years old.