1. TEKS 5.7D
Identify fossils as evidence of past living organisms and the nature of the environments as the time using models.

2. Study the diagram below.1 2
soil
sandstone
conglomerate
shale
limestone

3. Fossil 1 is probably…. Younger than fossil 2 Older than fossil 2
Formed in metamorphic rock
D. Formed in igneous rock 1 2
soil
sandstone
conglomerate
shale
limestone

4. The correct answer is A.
Fossil number 1 is younger than fossil number 2.
The bottom layer of rock (limestone) formed before the layer of shale.
Fossil 1 is in the shale. 1 2
soil
sandstone
conglomerate
shale
limestone

5. B, C, and D are incorrect Older than fossil 21 2
soil
sandstone
conglomerate
shale
limestone
Older than fossil 2
Formed in metamorphic rock
D. Formed in igneous rock
because
B The layer of limestone was formed before the layer of shale.
C Sandstone, conglomerate, shale, and limestone are sedimentary rocks.
D. Fossil number 1 is in shale which is a sedimentary rock.

6. Fossils were found in these four layers of rock.1 2 4 3

7. What can you tell about this environment over time?
Each layer shows evidence of a different environment
Mammals dominated the environment
The environment has always been dry
Some layers show wet environments and others show dry environments 1 2 4 3

8. The correct answer is D. Layer 1, 3, and 4 are wet environments.
Layer 2 is most likely a dry environment. 1 2 4 3

9. The most likely place to find a fossil is in ________ rock.
smooth rock
rough rock
volcanic rock
Sedimentary rock D C A B A B

10. The correct answer is A. A
Sedimentary rock
Most fossils form when a dead plant or animal is buried quickly by sediments. As the sediments harden the remains become trapped in rock and form a fossil.

11. Answers B, C, and D are wrong.
These answers are incorrect because …
Sedimentary rock can be rough or smooth depending on how much and how it has been weathered.
Volcanic rock from lava flow produces a lot of heat and pressure that will destroy living material so a fossil cannot form. B
Rough rock C
Smooth rock D
Volcanic rock

12. What can you infer about an animal from a fossil of its jawbone?

13. A. How big its feet were B. Whether it walked on four or. two legs C
A. How big its feet were B. Whether it walked on four or two legs C. The approximate size of the animal from which it came D. Whether it was a herbivore, carnivore, or omnivore

14. The correct answer is C.
The size of the jawbone would indicate the approximate size of the animal from which it came. If teeth were in place, they would indicate what the animal ate. The jawbone could also give clues to the size and shape of the animal’s head.

15. These answers are incorrect because …
The jawbone will not indicate the size of the feet of the animal.
You would need fossils of the feet or fossils of the track of the animal to determine the number of feet.
The teeth would have to be in place to indicate what the animal ate.