Fossils

The Green River Formation in Wyoming is made of layers of rock that contain fabulous fish fossils. What most likely occurred to allow the fish to be preserved so well?

• The fish got buried in sediment.

• Animals ate the fish so the bones were clean and ready to turn to fossils.

• The fish moved along until it landed in a safe quiet place.

• The temperature increased until conditions were right to form fossils.

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 above.

What have scientists determined about woolly mammoths?

• The more fur on their body, the older they were.

• They were able to live in the very cold climates of the ice age.

• Their fur helped block spears from hunters.

• The fur made their bodies too warm and caused them to become extinct.

Which could result in a mass extinction?

• heavy thunderstorms

• no rain for long periods of time

• alternating dry and wet seasons

• rainy seasons followed by short periods of dry weather

Jeffery visited the La Brea tar pits in California with his family. He learned that the plants that lived in the area 40,000 years ago were not much different from those that live in and around Los Angeles today. What does this information tell scientist?

• None of the plants has changed since that time.

• The animals that lived then are the same now.

• The climate is not much different from what is was back then.

• Yearly rainfall has increased steadily.

Janice 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 Janice find?

• a mold and a cast of a shell

• a shell frozen in rock

• a shell preserved in amber

• a trace fossil of a seashell

What may have caused 75% of Earth's organisms to become extinct approximately 65 million years ago?

• glaciers

• disease

• a meteorite impact

• the temperature became too warm

What is a mass extinction?

• one species evolves into another similar species

• all members of the same species die pout unexpectedly

• large numbers of certain species become extinct overnight

• many species become extinct over a short period of geologic time

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

• a snailt 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 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 have scientists determined about woolly mammoths?

• The more fur on their body, the older they were.

• They were able to live in the very cold climates of the ice age.

• Their fur helped block spears from hunters.

• The fur made their bodies too warm and caused them to become extinct.