Fossils

1
Fossils
Tell of Long Ago
2
Fossils are animals or plants that lived a very
long time ago.After they died, they turned to
stone.
3
How do animals and plants become fossils when
they die?
Most dontthey just rot and disappear, often in
swampy forest soil called peat.
4
Sometimes leaves fall in the peat. The leaf may
rot away, but the mark of its shape is left.
The peat with the leaf hardens into a rock,
called coal. Coal is a fossil too.
5
Sometimes animals die and only their bones are
left, covered in mud.
Thousands of years go by, the mud piles up in
layers and the weight of the mud presses down on
the bones. The mud turns to rock.
6
As that happens, ground water seeps through the
changing layers of mud.
7
Minerals are dissolved in the water.
The water seeps into all the tiny holes in the
fish bones.
8
After a very long time the bones turn to stone
and become a fossil.
9
Some fossils are actual parts of plants or
animals that have turned to stone.
Sometimes a fossil is only an imprint of a plant
or an animal.
10
Not all fossils are found in stone.
Some are found in the frozen ground of the
Arctic, like the bones of the ancient mammoth.
11
Millions of years ago, a fly was caught in the
sticky sap of a tree.
The sap hardened and became a fossil known as
amber. The fly was preserved in the amber.
12
We can learn many things from studying fossils.
Fossils tell us about the past.
13
More About Fossils(right-click to open
hyperlink)

• How fossils are made
• What is a fossil?
• What makes a fossil movie
• Fossil Horses in Cyberspace
• Introduction to the Annelida
• Open Court Reading 2002, Level 2, Unit 4
• Created by Carol Potter, 2005