Past Environments Based on Fossil Evidence

Researchers found seashell fossils, including those from mollusks and coral, in a

rock formation high in the Rocky Mountains.

Which statement BEST explains why seashell fossils can be found on some

mountains?

• The rocks formed underwater.

• Rivers carried the rocks up the mountains.

• The area was a sand dune that hardened as it was covered by water.

• The mountains split to form canyons that contained organisms with shells.

Researchers find fossilized remains of cold-water fish species in a rock formation

near the equator.

Select TWO possible explanations for this discovery.

• The Earth's climate was much colder in the past.

• The equator was located in a different position.

• The fish species evolved to prefer warmer waters.

• The rock formation moved from a colder region.

Which statement BEST describes how the fossil bones of a dinosaur are formed?

• The dinosaur became trapped in amber.
• The dinosaur was covered in sediment.
• The dinosaur was frozen in ice.
• The dinosaur stepped in wet mud.

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2

A construction crew digging a foundation in a desert area discovers multiple fish fossils

embedded in the rocks.

Which conclusion about this area's past environment is BEST supported by this fossil evidence?

• The area was once covered by water.

• The area was always a desert.

• The area experienced frequent sandstorms.

• The area was covered by dense forest.

Your class goes on a field trip to a science museum. In the fossil exhibit, you see a display of a

mud core taken from the bottom of an old lake. The guide shows you how scientists found tiny

fossilized pollen grains in different layers of the mud.

The museum guide asks, "What can these tiny fossil pollen grains tell us about the past?"

Select TWO correct answers:

• What kinds of plants grew near the lake long ago

• The exact temperature of the lake water

• How the types of plants changed over time

• How deep the lake was

In order for a fossil to form, which of the following events must happen FIRST?

• Slowly, minerals in the water replace the bone.
• Sediment covers the bone.
• An animal dies.
• The bone is no longer a bone, but a rock copy.

Tags

NGSS.MS-LS4-1

Your class is studying fossils. Your teacher shows you a fossilized jaw with teeth from an animal

that lived millions of years ago. The teeth are flat with ridges, similar to a cow's teeth today.

Based on the fossil evidence, what can we guess about where this ancient animal lived and what it

ate?

• It lived in a desert and ate cactus plants.

• It lived in an ocean and ate small fish.

• It lived on grasslands with some trees and ate plants.

• It lived in an icy area and ate meat.

Researchers found seashell fossils, including those from mollusks and coral, in a rock formation

high in the Rocky Mountains.

Which statement BEST explains why seashell fossils can be found on some mountains?

• The rocks formed under water.

• Rivers carried the rocks up the mountains.

• The area was a sand dune that hardened as it was covered by water.

• The mountains split to form canyons that contained organisms with shells.

Your class visits a cliff far from the ocean to study rock layers. In one layer, you find many

fossilized seashells. In a higher layer, you find fossilized leaves from land plants.

What does the change in fossils from the lower layer to the upper layer suggest about how this

area's environment changed over time?

• The area changed from land to ocean.

• The area changed from ocean to land.

• The area remained ocean the entire time.

• The area remained land the entire time.

Fossils of marine organisms, such as fish and coral, were discovered in a desert region.

Scientists also found layers of sandstone and limestone in the area. Based on this evidence, which

process MOST LIKELY transformed the environment into what it is today?

• Erosion of forests into deserts over millions of years

• Gradual drying of an ancient ocean, leaving behind desert conditions

• Volcanic eruptions that replaced water with molten rock

• A sudden ice age that froze the water and created sandy plains