EQ: How do fossils show evidence of the changing surface and

climate of the earth?

Lesson 21

Fossil Tracks

Discussion…

Write down four observations and one inference based on this picture.

• Write down four more observations and a new inference.

• Based on this information, what you think has happened?

• Make at least 3 more observations and your final inference.

Let’s Discuss Our Findings

• Answer these questions in complete sentences on your notebook entry…

1.Did everyone have the exact same inference? Explain why or why not.

• 2. How is this activity like the fossil record? (Hint: think of the fossil record as a puzzle)

Fossils

• A fossil is the remains or evidence of a once-living thing.

• Most fossils are found in sedimentary rocks.• Fossils can reveal what an area on Earth looked

like millions of years ago.• They also can help us understand the type of

climate that area experienced millions of years ago.

• The upper layers of rock are younger than the lower layers of rock.

Changing Climates

• Scientists have found evidence of fossils of corals in Arctic waters.

• Corals can live only in warm water.

• The fossils indicate that a long time ago the Arctic was a warm place.

• Scientists found fossils of alligators in Canada.

• Alligators live in warm swampy areas.

• Conclusion is that Canada was once warm and swampy.

Changing Surfaces• Fossils also provide clues to how Earth’s surface may have changed

over thousands and millions of years.• Scientists have found seashells high in the foothills of the Andes

Mountains.• Two hypotheses:

- Either, the sea once rose to cover the hills- Or, the hills rose from under the sea.

• Regardless of which hypothesis is correct, we know that the surface of this part of the world has changed over time.

Quick Check

What can fossils reveal about Earth’s past?A. Only changes in Earth’s climate over timeB. Only changes in Earth’s surface features over timeC. Changes in Earth’s climates and surface features over timeD. Present climates and surface features of Earth

Quick Check

A seashell on top of a hill MOST LIKELY indicates that

A. The hill was once under the sea.

B. Sea animals once lived on land.

C. Seashells are not parts of living things.

D. All hills were once under water.

Quick Check

Finding a fossil of a palm tree in Alaska could be explained if the climate of Alaska

A. was once colder than it is now.

B. has always been the same as it is now.

C. was once warmer than it is now.

D. is warming up now.

Quick Check

If you found a fossil of a freshwater animal in a desert, what could you conclude?A. The ocean once covered the desert.B. The desert rose from the sea.C. The desert sank beneath the ocean.D. A river once flowed through the

desert.

Quick Check

The fossil of a tiny horse is found in a layer of rock below the fossil of a larger horse. What can you conclude?

A. The tiny horse fossil is younger than the larger horse fossil.

B. The tiny horse fossil and the larger horse fossil are the same age.

C. The tiny horse fossil is older than the larger horse fossil.

D. The larger horse fossil is older than the tiny horse fossil.