- A bizarre new competition among avocational
paleontologists involves racing to collect representative
fossils of a set taxonomic groups. You can start anywhere
in the northeast, you can collect the fossils in rocks of
any age, and you mustn't exceed the speed limit. This means
to win you have to be efficient about your route and know
where to go. You must find the following: 100 bivalves 100
trilobites 5 crinoids 5 stromatolites 100 gastropods 100 brachiopods
5 blastoids 5 barnacles 100 cephalopods 100 bryozoans 5 cystoids
5 shark teeth A local natural history museum sponsors you
with a driver and travel funding. Make a plan to enter the
race. Give the route you would take that would make it likely
you could find enough of each of these organisms quickly.
Given highway speed limits, collecting 10 hours/day, how much
time do you think it would take to collect these fossils?
Explain your assumptions and calculations. What factors would
influence this time?
- Nova, the Public Broadcasting System science
documentary specialists, hear that you won the race. They
like the action of the race, but had been planning to create
a movie on the history of life. Thus they wish to sponsor
another race, this time collecting the organisms sequentially
through geologic time rather than solely by kind of animal.
Explain how you would change your route to collect fossils
from oldest to youngest. In this race, one must find just
one specimen of each of 3 kinds of fossils from the list in
part (1) for each geological period in order from the Cambrian
to the Quaternary. How fast could you do it? How do these
fossils fit into the following geologic events? (1) the Grenville
passive margin (2) the Taconic converge, (2a) interval (Silurian-Early
Devonian) between Taconic and Acadian (3) the Acadian convergence,
(3a) interval (Mississippian-Early Permian) between Acadian
and Alleghenian (4) the Alleghenian convergence, (4a) interval
(Early-mid Triassic) between Alleghanian and rifting (5) the
rifting apart of Pangea, and (5a) interval (mid-Jurassic-late
Jurassic) between rifting and creation of Coastal Plain (6)
the Coastal Plain passive margin and shaping by erosion of
many of current land-forms (7) Pleistocene glaciation and
Holocene post-glacial.
- Given your new celebrity status, the local
fossil club calls you to give a talk on the history of life
from the local area, based on fossils. You patiently explain
that this isn't possible with fossils, because no one place
has anywhere near a complete record. However, you can guess
what happened, since missing rock sometimes indicates the
presence of land environments, and these land organisms may
have been recorded elsewhere. You promise to give them a presentation
about this. Write a script for a nontechnical talk, giving
your estimation of the history of life (the land and sea)
in your neighborhood. Point out what we know from local fossils
and what we know from elsewhere. Choose illustrations for
your talk.
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