1. The Stories Fossils Tell

2. Can you name the 4 types of Fossils ?

3. Name the 4 types of Fossils
Mold
Trace
Casts
True form

4. Describe how Mold Fossils are formed.

5. Mold Fossils -are usually formed in sediment -organisms like shells, leaves or bones, are covered with mud -over time mud hardens -water enters mold and dissolves dead organism -mold fossils are HOLLOW on the inside

6. Describe how Casts Fossils are formed.

7. Casts fossils -need a mold fossil first -after organism dissolves and leaves an empty space -the empty space fills with minerals –-as time passes it hardens to form a cast fossil

8. Describe how Trace Fossils are formed.

9. Trace Fossils -are markings left by animals -examples include leaf prints, footprints, eggs and nests -Trace fossils are good for scientists to use to understand animals’ BEHAVIORS

10. Fossil footprints have yielded information about: Speed and length of stride whether they walked on two or four legs the bone structure of the foot stalking behavior (a carnivore hunting a herd of herbivores) the existence of dinosaur herds and stampedes how the tail is carried (few tail tracks have been found, so tails were probably held above the ground)

11. Describe how True Form Fossils are formed.

12. True Form Fossils True Form fossils are formed when the animals soft tissues or hard parts did not decay over the years because they are trapped in sap that hardens to become amber. This evidence gives scientists the BEST observation of past plants and animals.

14. Fossils start out as living things.
The organism can be either a plant or an animal.
(read from slide)

15. When the organism dies . . .
The soft parts that are exposed to air decompose quickly.
Hard parts like bones, shells, or wood, don’t decompose as quickly. They have the greatest chance of becoming a fossil.
(read from slide)
Ask children what it means to decompose. (to breakdown, to rot, to disintegrate)
You might have your students feel their own hand for soft parts (skin, tendons, muscles) and hard parts (bones and joints)
Some fossil beds contain soft-bodied fossils. To find out more, do a web search for “Burgess Shale”.

16. The organism may be buried in layers deep in the earth
The organism may be buried in layers deep in the earth. These layers might be composed of mud, lava or water.
Sediments
Basalt
Fossil layer
(read from slide)
When an organism is covered, it is protected from weather damage, rotting or decay and from scavengers who might eat the dead organism.
Layers shown from the top
Top two layers are sediment
Basalt
Fossil layer
Sandstone
Sedimentary
Sandstone
Basalt
Coal
Sedimentary Rock
Basalt

17. Scientists sometimes dig in the Earth looking for fossils.
Sometimes fossils are found on the surface of the earth. They become exposed by:
Weathering
Erosion
Earthquakes
The activity of humans
Once fossils are found, scientists often dig in the same area to find other fossils.

18. How do fossils help us learn about the past?
Point out that the scientist in the picture is making observations of an animal skull. From observations, the scientist makes inferences about the environment and life of long ago.
Observation: The skill of recognizing and noting facts or occurrence in the natural world.
Inference: The skill of arriving at a decision or conclusion (best guess) after examining all of the known facts and information.

19. Thinking like a paleontologist
A paleontologist is a scientist who studies fossils. Paleontologists and many other scientists use inference – this is not what they actually observe but what they think about their observations.
This picture shows a scientist working in a lab. What tools is the scientist is using? (microscopes, lights, magnifying glasses, small hand tools.
What fossil evidence do they see? (skull on shelf, bones on table, specimens on shelves)

20. Let’s practice making inferences about living things.
Would the tree live in this environment?
Look at these pictures of things that come from a tree. Make a prediction about the environment where you would find this tree.
(read from slide)
Students are not expected to know or learn the answers to these questions. The emphasis is on that to answer the questions, you need more information about the plants and the environment where the plants are found. Scientists who study fossils use their knowledge about current and extinct plants and animals to make predictions about new discoveries.
Questions a scientist might ask?
What do I already know about similar plants or animals?
Where can I go to find out information?
What else has been discovered in this area?
… or, would the tree live in this environment?
This is more difficult isn’t it? Why? What would help you decide on the correct environment?

21. Can you be a paleontologist?
This is the environment where you are looking for fossils.
(read from slide)
BACKGROUND FOR THE TEACHER: The fossil, that of a fish, lived in a lake or ocean certainly not the sand dunes where it was found by scientists. This should tell the students that the area must have been covered by water in the past.
Here in an example of the kinds of fossil your team has found. What do you think the environment might have been like in the past?

22. Let’s try another example!
(read from slide)
BACKGROUND FOR THE TEACHER: The plant (fern) fossils would indicate a moist, shady environment, certainly not the desert where it was found.
You just found the plant fossils, on the left, in an area where it is now hot and dry like the picture on the right. What predictions can you make about what the environment might have been like in the past?

23. “Once Upon a Time” is not just for fairy tales.
Asian Elephant
Wooly Mammoth
(read from slide)
Have students compare the wooly mammoth and the Asian elephant. How are they alike and how do they differ. As a group you might want to create a Box & T-chart on the overhead, flipchart or whiteboard. Remind your students that the Box & T-chart is based upon observations only not inferences.
EXAMPLE Of BOX & T-CHART
Compare and Contrast with a Box and T-Chart
Large white tusks
Similarities Lump on head
Long, flexible trunks that touch the ground
Big body shape
Asian Elephant Wooly Mammoth
Short Hair Long hair
Differences Less curved tusks More curved tusks
No hump on back Large hump on back
Smaller ear flaps Larger ear flaps
How are these two animals the same?
How are they different?

24. The wooly mammoth is the ancestor of the modern Asian elephant.
(read from slide)

25. Once Upon a Time – A Look at the Horse
Horse B
Horse A is an example of an ancient horse. Over time Horse A evolved to look like Horse B, a modern day horse.
Background Information
Horse A - Hyracotherium – 55 million years ago (Eocene Epoch)
This small dog-sized animal represents the oldest known horse.   It had a primitive short face, with eye sockets in the middle and a short diastema (the space between the front teeth and the cheek teeth). Although it has low-crowned teeth, we see the beginnings of the characteristic horse-like ridges on the molars. Hyracotherium is better known as "eohippus" - which means "the dawn horse."   The name also refers to the fact that it lived during the Eocene.
Horse B - Equus – 5 million years Pliocene to Present
Equus is the only surviving genus in the once diverse family of horses.   Domesticated about 3,000 years ago, the horse had a profound impact on human history in areas such as migration, farming, warfare, sport, communication, and travel. Species of Equus lived from 5 million years ago until the present.   Living species include horses, asses, and zebras.   Fossils of Equus are found on every continent except Australia and Antarctica.
Horse A

26. Change Over Time – A Horse’s Foot
Note how the distance of the wrist bones from the ground changes. What else has changed?
(Read slide to students)
What to look for:
Total length of foot
Number of toes making up the foot
The size of the hoof covering the foot
wrist
Adapted from Florida Museum of Natural History. For more information visit their website at

27. Let’s Look More Closely
(Read the slide to the students)
BACKGROUND FOR THE TEACHER: The bones became longer and more streamlined, enabling horses to run faster to avoid predators.
The central toe of horses became increasingly stronger while the "side toes" became less important and are virtually lost in the modern horse.
Reduction and loss of side toes minimizes the weight at the extreme end of the foot.   The horse's limb may move faster.
Changes:
Middle bone (toe) becomes more dominant
Side toes become virtually lost
How have the bones in horse feet changed over time? Why might this have happened?
Adapted from Florida Museum of Natural History. For more information visit their website at

28. Wrap-Up Fossils are formed under very special conditions.
They give us clues about what life was like long ago.
Fossils also give us clues about the environment from a long time ago.
They help us understand that plant and animal species change over time.
(Read slide to students)

33. Group 1, group 3, group 4, group 2 Group 2 is the youngest.

34. Rivers deposited the shells
The region was once under an ocean environment
Early Native American left them there.

35. b.The region was once under an ocean environment