Fossil Notes
Fossils: Preserved remains or impressions of
organisms from the Earth’s past.
Fossil Types
 Remains: Part of the living organisms that remain
together after the organism’s living material has
decomposed
 Trace Fossils: Tracks, trails, burrows, or nests that
show the activity of on organism
Unaltered Remains
The organism’s structure has not been decomposed or
changed
Unaltered Fossils can be preserved in
 Tree resin (amber)
 Tar
 By mummification
 By freezing
Altered Remains
Fossils are changed when they are preserved
Mineral matter seeps into the organism and replaces
living cells after the remains have been buried.
Ex. Bones, teeth, shells
Molds/Casts
The impression of an organism that is left behind is a mold.
After a mold is made sand or other material fill the mold,
and over time hardens and creates a replica of the original
organism this is a cast.
Why are fossils important to scientists?
 Helps us to figure out what organisms lived on Earth
 Helps us to figure our the events of the Earth’s past.