Directions: Read each story and answer the questions below by checking the appropriate box.
Paleontologists, archaeologists and other scientists digging into the past base conclusions about their finds on partial evidence. They have to be able to tell the difference between a fact and an inference. Here's your chance to practice scientific reasoning. Suppose you are in charge of a group of paleontologists digging at a fossil site.
Someone screams "Eureka!" When you go over to investigate, you observe the fossilized bones pictured in
Diagram A.
Based upon your observations of the bones, which of these statements is a fact and which is an inference?
Remember, an inference is something you assume from your observations. For example, you see a person sitting on a chair with their eyes closed. Fact: they are sitting on a chair. Inference: they are tired.
1. The fossil find includes a jaw bone.
2. The person who screamed "Eureka" uncovered a fossil find.
3. This animal had sharp, dagger-like teeth.
4. This animal ate other animals.
5. This animal used its sharp claws to kill prey.
6. This animal walked on land.
7. This animal was a vertebrate.
8. This animal had fur or other body covering to keep warm.

Geologists and paleontologists rely on what they find in rocks to confirm their theories. But rocks can't talk, so sometimes the conclusions must be inferred.
Examine the rock sample shown in Diagram B. It was removed from the ground exactly as illustrated (the top portion of the rock was nearest the surface). If something is near the surface it will be younger than the layers below it. The farther down the layers, the older the layer is. The animals also change in their complexity as you go from top to bottom. The fossils closer to the surface are most likely to be more complex than the fossils below them.
Classify each of the following statements as an inference or a fact.
1. The rock sample has seven layers.
2. The oldest layer is found at the bottom.
3. The youngest layer is found at the top.
4. This sample is a sedimentary (or layered) rock type.
5. Dinosaurs probably existed when these fossilized organisms were alive.
Questions
1. Which layer of fossil is probably older, layer #1 on top or layer #4 below?
2. Which fossil is probably the most recent, layer #2 or layer # 6?
3. Which fossil is probably the most complex, layer #5 or layer #3?
4. What events (natural or caused by man) could alter this rock arrangement? How might the changes confuse our study?