PALEONTOLOGY & EVOLUTIONARY BIOLOGY (Ch. 18.1-18.3)

Question 1

The most common type of fossil that shows the original shape of the fossil to the cellular detail

Answer 1

Permineralization and Replacement

Question 2

These fossils show the surface shape but give no information on internal details

Answer 2

Natural Molds

Question 3

These fossils form when unfilled space is infiltrated, filled, and harden into rock

Answer 3

Casts

Question 4

These fossils show body shape and can tell us about behavior. there are three types of this type of fossil.

Answer 4

Trace fossils. Trackaways, Coprolites, Burrow or Den

Question 5

These fossils are preserved in resin. These fossils give us the most complete picture of ancient life.

Answer 5

Amber and Freezing

Question 6

How much of life on earth is extinct? What do fossils tell us?

Answer 6

99% is extinct. Fossils tell about extinct phenotypes, when groups of organisms appeared and diversified, and transitional features that help us understand evolution.

Question 7

Any trace of an organism that lived in the past

Answer 7

Fossil

Question 8

Why is the fossil record more complete in the Northern Hemisphere?

Answer 8

Historically, the Northern Hemisphere has been sampled more than the Southern Hemisphere (Historical Bias). Also, there is less vegetation allowing for easier access to fossils.

Question 9

How do paleontologists find fossil localities? How do they know how old rocks are?

Answer 9

Using previous sites, or discovering new sites with geologic maps. Once fossils are found they use radiocarbon dating to see how old the rocks are from the site.

Question 10

Common ways to prepare a fossil for a study

Answer 10

Thin sectioning, CT scanning, and Cellulose Acetate Peel Technique.

Question 11

Tools used to prepare a fossil for a study

Answer 11

Lapidary ( a saw that grinds rock) and an Air Scribe that breaks rocks.

Question 12

What three features of species do fossils need to rely on? Why do some depositional environments preserve more complete fossils than others?

Answer 12

Durability, burial, and lack of oxygen. This is because sediment will preserve the fossils well unlike other areas that are too arid and rapidly eroding like mountain ranges. Hard-structured fossils are preserved well in rivers deltas, beaches, floodplains, marshes, lakeshores, and lakeshores, and seafloors.