Science 6 Grade Chapter 8 Lesson 3

Front 1

A period in which a large number of species become extinct.

Back 1

mass extinction

Front 2

________ are evidence of the kinds of organisms that lived in a place during a certain period of time.

Back 2

Fossils

Front 3

scientists know more about _________ ecosystems than about ancient land ecosystems.

Back 3

ancient saltwater and freshwater

Front 4

For the last 40,000 years, mammals, birds, seeds, and insects moving over the sticky tar have become trapped (where)

Back 4

La Brea Tar Pits in Los Angeles, California

Front 5

How can you find out what kinds of ecosystems existed in your state in the past?

Back 5

You can examine fossils

Front 6

Extinct animals found in the La Brea Tar Pits include saber-toothed cats, mammoths, and several bird species. These animals became extinct 10,000 to 4000 years ago. The only way for scientists to learn about these species now is ___________

Back 6

through the fossil record

Front 7

By studying the fossil record, scientists have found that the kinds of organisms ______________________.

Back 7

that have lived on Earth have changed greatly over time.

Front 8

early in the history of life on Earth, many kinds of _______A_______ animals roamed the oceans. There was very little ______B____.

Back 8

A. armored fish, lungfish, sharks, and other marine animals
B. land life

Front 9

early in the history of life on Earth, many kinds of armored fish, lungfish, sharks, and other marine animals roamed the oceans. There was very little land life. As a result, this period of time is often called the ___________

Back 9

Age of Fish

Front 10

For example, a mass extinction could be caused by ______what_______

Back 10

the impact of a large asteroid, a decrease in the food supply, a loss of habitat, a climate change, or all of these.

Front 11

dinosaurs dominated the land for a period known as __________

Back 11

the Age of Reptiles.