FossilsFossilsFossilsFossils

Question of the DayQuestion of the DayQuestion of the DayQuestion of the Day

Question: How much of a 100g uranium sample is left after 2 half lives?

Answer: … … …

Turn In: - p. 588 CYU 1 – 6

-Half Life Cubes Lab

How to Fossilize Yourself:

Types of fossilsBody fossils: bones, teeth, shells, tree trunks etc

Trace fossils: footprints, worm burrows, leaf prints etc

Who Studies Fossils?Paleontologists: scientists that study fossilsPaleo- = oldMany work with microscopic fossils

How Fossils FormAnimal or plant diesIF

Nothing eats the organism right away AND

The organism/ footprint doesn’t get washed away AND

the organism is buried in sediment (sand, mud etc) very soon after it dies (ex: sinking in mud) AND

There is no oxygen in the surrounding environment AND

The chemicals in the bones/ plant material are replaced by other minerals

THEN the bones will become fossils

Things to Remember about FossilsForm in sedimentary rock ONLYmillions of years oldnot the actual bone

they are a “model” of the original bone/footprint made of minerals

very, very raremany conditions have to be perfect to form them

(most organisms do not become fossils)

Fossil FootprintsPurpose: To make observations about a set of footprints and to determine four scenarios based upon those observations.

Procedure: Utilizing the 4 scenarios of footprints, make at least 2 observations and 2 inferences for each scenario.

1

2

3 4

Blood on the Tracks