Fossils

What is the most likely reason the saber-toothed cat became extinct?

• The temperature became too cold.

• Saber-toothed cats were hunted by other animals.

• The area in which they lived became an ocean.

• Animals they depended upon for food became extinct.

What is a scientist who studies fossils called?

• a biologist

• a botanist

• a paleontologist

• a physicist

Scientists know that the continents have moved across Earth’s surface throughout history. What is the name of the idea that first described the movement of continents?

• plate tectonics

• continental drift

• continent movement

• landform change

Scientists use fossils to describe how all of the environments on Earth have changed over time. Which fossil discovery represents a change in the environment where the fossil was found?

• fish in rocks on top of a mountain

• seashells in the sand at the beach

• horse bones in soil in the prairie

• polar bear bones in Alaska

Which fossil’s relative age cannot be determined based on its position?

• a fossil found in every rock layer

• a fossil found in the bottom rock layer

• a fossil found in the top rock layer

• a fossil found in a middle rock layer

Which can you conclude about a fossil that appears in many rock layers?

• The fossil is useful for scientists.

• The organism lived in many places in the world.

• The organism lived for a geologically short period of time.

• The organism lived for a geologically long period of time.

Kyle found a rock and used a hammer to split it open. One half of the rock had a raised shape of a shell. The other had an impression of the shell. What type of fossil did Kyle find?

• a shell preserved in amber

• a mold and a cast of a shell

• a shell frozen in rock

• a trace fossil of a seashell

Which of the following fossils would make a good index fossil?

• a snail that lived in Ohio, in a small population during the Cenozoic

• a trilobite that lived in all areas east of the Mississippi River, in large populations during the end of the Paleozoic

• a tree fern that lived in northeastern Pennsylvania, in a small population during the Mesozoic

• a magnolia flower that lived in the eastern United States, in large populations during the Cenozoic

What can the presence of fossils tell us?

• Oceans once covered what is now dry land.

• Forests once covered what are now deserts.

• Glaciers once covered much of North America.

• All of the answers are correct.

Plants and animals become fossilized in several different ways. Which object fossilized most recently?

• A

• B

• C

• D