Fossils
Wooly Mammoth
The wooly mammoth has been found in ice, its body
preserved completely. Some mammoths have been
found with food still in their stomach.
Wooly Mammoth
Fossils in
Amber
Fossils in
Amber
Tar Pits
Tar Pits
Fossils Webquest
www.ucmp.berkeley.edu/education/
explorations/tours/fossil/5to8/Intro.
html
Fossils
• Fossils: remains of once living
things buried in rocks of
Earth’s crust.
• Only a fossil if it is found in
rock, usually sedimentary
rock.
Fossils
• 4 types of fossils
1. body fossils: actual
remains of living things
(bones, wooly mammoth).
2. trace fossils:
impression left by once
living things (footprints,
trails, burrows)
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Fossils
4 types of fossils
3. molds: form when
sediments bury an animal, the
animal or plant rots away, but
leaves behind a mold of its
original shape.
4. casts: minerals or other
materials fill in the mold and
harden into the original shape
of the organism.
Which is the oldest fossil?
Bottom layers are the oldest layers,
so they contain the oldest fossils.
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What do fossils tell us?
Tell us about Earth’s history.
Tell us about Earth’s history of climate and
geography changes.
Show how organisms evolved from their
ancestors to what they are today.
Shows major periods of extinction (for
example, a majority of the dinosaurs
appear to have gone extinct at the same
time)
The fossil record is NOT complete.
Fossils reveal climate change:
• The climate where we find fossils today
might not have been the same when the
fossils formed.
• Scientists especially look to the fossils of
plants, tiny organisms, and soil to study
ancient climate patterns.
Forams:
• tiny organisms that have a shell and live in
the ocean.
• What their shell is made of is determined by
the water temperature and whether or not
ice sheets exist nearby.
• Therefore, their shells tell us about what the
climate was like in the past 65 million years.
Plant Fossils
• We depend on plant fossils to tell us about the
climate, since their survival depends on certain
temperatures and amounts of precipitation.
• Differences in temperature and precipitation
will effect the size and shape of the leaves.
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Leaf shape in warm, wet climates are usually large
and thick.
Leaf shape in cool, dry climates are usually small
and thin.
Soil Fossils
• Paleosols, which is soil
preserved in rock helps us
know about seasonal
patterns, type of climate,
amount of precipitation,
and temperature ranges of
ancient time periods.
– Example: Red paleosols
represent a wet, warm
climate.
– Green or brown paleosols
represent a colder climate.