Key Idea.
Section 1
Geologists Read Fossil Clues
Fossils provide context that rocks alone might miss. Geologists use fossils to confirm their ideas about past environments. By identifying the type of organism preserved in the rock, scientists can infer the conditions that must have existed to support that life.
For instance, finding a marine organism in a rock layer proves that the area was covered by saltwater at the time the rock formed.
Section 2
Fossils Tell Environmental Stories
Every living thing is adapted to a specific habitat. Therefore, a fossil acts as an environmental indicator. The physical characteristics of the fossilized organism reveal where it lived.
An organism with structures for swimming indicates an aquatic environment, while an organism with structures for breathing air indicates a terrestrial (land) environment.
Section 3
Fossils Reveal Past Environments
When studying a rock layer, the specific combination of rock type and fossils tells a complete story. If a rock layer contains fossils of shells or fish, it provides strong evidence that the location was once an ocean or lake.
If a layer contains fossils of leaves or land animals, it indicates the area was dry land. These clues allow scientists to map how the environment of a specific location has changed over millions of years.
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Section 1
Geologists Read Fossil Clues
Fossils provide context that rocks alone might miss. Geologists use fossils to confirm their ideas about past environments. By identifying the type of organism preserved in the rock, scientists can infer the conditions that must have existed to support that life.
For instance, finding a marine organism in a rock layer proves that the area was covered by saltwater at the time the rock formed.
Section 2
Fossils Tell Environmental Stories
Every living thing is adapted to a specific habitat. Therefore, a fossil acts as an environmental indicator. The physical characteristics of the fossilized organism reveal where it lived.
An organism with structures for swimming indicates an aquatic environment, while an organism with structures for breathing air indicates a terrestrial (land) environment.
Section 3
Fossils Reveal Past Environments
When studying a rock layer, the specific combination of rock type and fossils tells a complete story. If a rock layer contains fossils of shells or fish, it provides strong evidence that the location was once an ocean or lake.
If a layer contains fossils of leaves or land animals, it indicates the area was dry land. These clues allow scientists to map how the environment of a specific location has changed over millions of years.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter