Chapter 18 Fossils and Geologic Time
Chapter 18 Fossils and Geologic Time
Chapter 18 Fossils and Geologic Time
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416 CHAPTER <strong>18</strong>: FOSSILS AND GEOLOGIC TIME<br />
are, in fact, fossilized dung, or feces. Figure <strong>18</strong>-1 shows modern<br />
footprints in a s<strong>and</strong> dune.<br />
ACTIVITY <strong>18</strong>-1 NEARBY FOSSIL BEDS<br />
Where are the nearest rocks that contain fossils? Local residents,<br />
park naturalists, or university professors may be able to help you<br />
locate fossils nearby. You may even be able to visit this location if<br />
it is on public l<strong>and</strong> or if you have the permission of the l<strong>and</strong>owner.<br />
Road cuts sometimes reveal fossils although there may be restrictions<br />
about stopping along busy highways. Be sure to investigate<br />
<strong>and</strong> secure any needed permission before you visit a fossil bed or<br />
collect specimens. As an alternative, some museums <strong>and</strong> universities<br />
have collections of fossils that you can visit.<br />
ACTIVITY <strong>18</strong>-2 INTERPRETING FOSSIL FOOTPRINTS<br />
Figure <strong>18</strong>-1 Modern footprints<br />
in s<strong>and</strong>—wherever<br />
footprints are preserved<br />
they give clues to events of<br />
the past.<br />
The pattern of footprints below was found in bedrock millions of<br />
years old. (See Figure <strong>18</strong>-2.) What do you think happened to produce<br />
this particular pattern of footprints? Propose a sequence of<br />
events that could account for the details you see in the footprints.<br />
Can you think of alternate explanations for this pattern? How can<br />
you determine which explanation is correct?
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