Question

fossils tell scientists a lot. fossils show how earth’s land and climate have changed. for example, the fossil of a shark’s tooth has been found on a mountain top. the fossil of a tropical plant has been found in cool, dry wyoming. these fossil clues show that the earth has changed over millions of years. what is now a mountain top may once have been an ocean floor. what was once a rain forest may now be a desert. fossils tell scientists what places on earth used to be like.
choose a word to complete each sentence. write each sentence so it makes sense.
land an ocean floor changed climate

1. a shark’s tooth fossil on a mountain top shows that the mountain may once have been ______.
2. fossils show how the earth’s ____ and ____ have changed.
3. fossils show that the earth has ______ over millions of years.

scientists found a woolly mammoth that had been frozen for 25,000 years.

Explanation:

1. From the text "what was once a rain forest may now be a desert. Fossils tell scientists what places on Earth used to be like" and the example of shark's tooth fossil on mountain top, we know sharks live in ocean, so the mountain may once have been an ocean floor.
2. The text says "Fossils show how Earth's land and climate have changed", so we fill in "land" and "climate".
3. The text "the Earth has changed over millions of years" and fossils show this change, so we fill in "changed".

Answer:

1. an ocean floor
2. land; climate
3. changed