Fossils

Question 1

What is a fossil?

Answer 1

Preserved evidence (remains or traces) of ancient life

Question 2

Body fossils

Answer 2

Body parts such as bonest, teeth, and skin

Question 3

Trace fossils

Answer 3

Evidence of their day-to-day activities such as footprints, trails, or burrows

Question 4

The only way an organism can become a fossil

Answer 4

If it’s protected from decomposition, scavenging, weathering, erosion, or any other process that may destroy the remains

Question 5

How are fossils made?

Answer 5

1. Over time, high spots wear down and low spots fill up (weathering breaks down rocks, and erosion transports sediment downhill)
2. The sediments are slowly buried and turn to rock
3. If we are lucky, sediments will also bury organisms and protect them from destruction
4. The more rapidly an organism is buried, the more likely it is to fossilize
5. Once an organism is buried, chemical changes may take place and turn it into a fossil

Question 6

9 ways to fossilize anything

Answer 6

1. Freezing
2. Mummification / Desiccation (Jerkify)
3. Encasement (Cover them in something sticky)
4. Replacement
5. Permineralization (Fill the void)
6. Petrification (Petrify it)
7. Recrystallization
8. Carbonization (Leave a film)
9. Molds and Casts
   1,2, and 3 make for the best fossils

Question 7

Encasement

Answer 7

• In amber (think of the spider about to eat a wasp example)
• In tar (Soft tissues break down, but the bones get “pickled. The original hard parts are still there, but turn black and smell like tar)

Question 8

Altered remains

Answer 8

When remains become fossilized due to chemical reactions that change their composition
Altered remains usually turn into stone

Question 9

Replacement

Answer 9

Original bone or shell material is dissolved and another mineral immediately take its place

Question 10

Permineralization

Answer 10

Water flows through pores and deposits minerals
- Common in bones

Question 11

Petrification

Answer 11

Permineralization + replacement
- Common in wood

Question 12

Recrystallization

Answer 12

Change in the crystal structure or the size of crystals (they get bigger)

Question 13

Carbonization

Answer 13

Bury it and squeeze all the water and other volatiles out until there is only a film of carbon left on the rock