FOSSILS
By Wendy McDonnal
VOCABULARY
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BODY FOSSIL
CAST
COPROLITE
DECAY
EROSION
EXCAVATE
EXTINCT
FOSSIL
FOSSIL RECORD
IMPRESSION
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MOLD
PALEONTOLOGY
PALEONTOLOGIST
PETRIFIED
TRACE FOSSIL
SEDIMENTARY ROCK
WHAT IS A FOSSIL?
WHAT IS THE STUDY OF FOSSILS CALLED?
WHERE ARE FOSSILS FOUND?
HOW DO FOSSILS OCCUR?
WHY STUDY FOSSILS?
WHAT IS A FOSSIL?
What is a fossil?
Fossils can be a:
~ PLANT
~ANIMAL
~Organisim
* Fossils are the remains or traces of animals or plants that once lived on earth and have
been preserved by natural causes in earth’s crust. It is important to know that not every
plant or animal becomes a fossil.
*The geological preservation processes take a long time. Many of the plants and animals lived
more than 10,000 years ago. However, some fossils which have been found are just several
hundred years old.
Fossils can be body parts of ancient organism such as bones, shells, teeth, or plant leaves.
*Some examples of fossils include:
A petrified (turned to stone) skull of a rodent.
A petrified bird’s nest.
A seashell mold in stone.
A carbon residue image of a leaf in stone.
A canine’s paw-print in a rock.
A stone cast of a beaver’s burrow.
A frozen (intact) wooly mammoth in an ancient glacier.
Fossil Shrimp (cretaceous) found in Lebanon
Priscacara liops fossil fish
Class Actinopterygii, Order Perciformes: Family Priscacaridae
Eocene
Green River Formation, Kemmerer, Wyoming (18 Inch Layer)
10 inches long
What is the study of fossils
called?
What is the study of fossils called?
~PALEONTOLOGY~
A person who studies fossils is called a Paleontologist.
Paleontologist at work, John Day Fossil Beds National
Monument. (NPS Photo)
A Palentologist excavates fossils at a dig site using large tools
such as picks, shovels, jack-hammers, or even explosives.
FRAGILE! Excavation of fossils must be done very carefully to
avoid breakage. Before removal, a quick-setting glue can be
applied using a brush or sprayer.
Paleontologist carefully chips rock matrix from a column of dinosaur
vertebrae.
Preparation of fossil bones of Europasaurus holgeri.
A Paleontologist working in a lab.
Before being transported to the lab, small fossils are packed carefully in
boxes or bags. Large fossils can be wrapped in paper or burlap with a
layer of plaster applied (like setting a broken bone).
Small hand tools: trowels, hammers, whisks, and dental tools.
Where are fossils found?
Where are fossils found?
*Fossils are found world-wide.
Some of the locations are:
~ Ocean Waters ~
http://legalplanet.files.wordpress.com/2009/04/ocean-turtle.jpg
Highest slopes of Mountains
Antartica
Adélie penguins chicks in Antarctica with MS Explorer and an iceberg at back ground. The image
was taken in January, 1999. MS Explorer sank on November 23, 2007 after hitting an iceberg in
Antarctica.
Sahara Desert
Leaving traces on soft sand dunes in Tadrart Acacus a desert area in
western Libya, part of the Sahara.
HOW DO FOSSILS OCCUR?
HOW DO FOSSILS OCCUR?
Fossilization Process:
*A plant or animal dies.
*Sediments (often in water) cover the organism and
preserve it so that it slowly decays.
*Over time, usually thousands of years, the sediments
harden into sedimentary rock around the remains.
*After the organism completely decays, an imprint and empty
space is left inside the rock – Mold.
*Sometimes minerals filter into the empty space and
harden into the shape of the dead animal or plant –
Cast.
Different kinds of fossils can be found.
Four types of fossils:
1. Mold fossil
2. Cast fossil
3. Trace fossil
4. True form fossil
MOLD FOSSIL:
A mold is an imprint of an organism or its trace.
For example, a shell can make an imprint in sand.
www.maine.gov/doc/nrimc/mgs/explore/fossils/past.shell.jpg
CAST FOSSIL:
A cast fossil is formed when a mold fossil is filled with sediment.
Ammonite
Photograph of a fossil ammonite Jeletzkytes spedeni taken by
Dlloyd. The specimen is from the Maastrichtian (UpperCretaceous) Fox Hills Formation. Locality - South Dakota, USA.
Matrix free specimen, 7.5 cm (3") in diameter, displaying pearly
aragonite preservation of the shell.
Trace fossil:
A trace fossil can be footprints hardened into stone, burrows, or coprolite (animal
poop).
Footprint impressions are left from an animal crossing a
wet surface of sediment which later hardens into rock.
True form fossil:
Ice Age mammoths from approximately 35,000 years ago were frozen
in North America or Siberian Tundra. They were preserved so well
that their last meals remain undigested in their stomachs!
www.no-pest.com/WoollyMammoth.htm
Insect Fossil
http://facstaff.gpc.edu/~pgore/myphotos/fossils/insect1.jpg
Many insects have been found in Amber – sticky tree sap.
More than 250,000 fossils have been recovered from
Rancho La Brea
Saber Tooth Cat
Species: Smilodon fatalis.
Age: Pleistocene.
Location: Rancho La Brea, California, USA.
Size: 6 feet 8" long. [Scale 1:1]
Why should we study fossils?
Why should we study fossils?
*We can learn about plants and extinct
animals from the past, such as dinosaurs.
*We can learn about the history of earth.
*We can learn about the environment which
the organisms lived in.
*We can learn what impact climate change has
on living organisms.
RESOURCES
John Day Fossil Beds National Monument www.nps.gov/joda
www.fossils-facts-and-finds.com/how_are_fossils_formed.html
www.enchantedlearning.com/subjects/dinosaurs/dinofossils/Fossilhow.html
www.learnerscience.com/docments/fossilsciencefairprojects.html
www.tarpits.org/education/guide/index.html
www.nasmus.co.za/PALEO/jbotha/paleo101.htm
www.ucmp.berkeley.edu/education/explorations/tours/fossil//index.html
www.ucmp.berkeley.edu/education/explorations/tours/fossil/guide/guide.html