Intro to Fossils

Which of these is an example of a body fossil?

• woolly mammoth footprints

• a T. Rex bite mark

• a dodo bird nest

• a shark tooth

In order to become a fossil, specific conditions need to be met. An organism needs to die in the right place. It must avoid scavengers and decomposers that would destroy its remains, and it needs to have hard body structures. Soft body structures will decay. Even if a fossil does form, it might not be found. Fossils are sometimes crushed, weathered, eroded and even melted before they are ever discovered. Based on the passage, which of these best describes fossils?

• rare to find and hard to form

• often formed but never found

• always crushed and often soft

• common to find and easy to form

Tags

NGSS.MS-LS4-1

Which of these is most likely to fossilize?

• a jellyfish’s very soft body

• fruit with a high water content

• a crab claw, which is very hard

• a horse’s mane, which is made of hair

Fossils can tell us a lot, but they can’t tell us everything. Think of everything you know about what a mouse looks like, its diet and behavior. If mice went extinct, what parts would fossilize? Its tail, fur and organs would not. They are too soft to be preserved. Future paleontologists would have to make a guess about what their brain looked like by studying their skulls. Paleontologists wouldn’t know what mice fur looked like, what colors it could be or it it had a pattern. As new fossils are added to the fossil record, we learn more. But Earth’s history still holds many mysteries.

The fossil record can best be described as

• too large.

• unhelpful.

• incomplete.

• not growing.

Tags

NGSS.MS-LS4-1

What is the term for the preserved remains or traces of ancient organisms?

• Minerals

• Fossils

• Crystals

Tags

NGSS.MS-LS4-1

Match the following terms to their definitions

• Empty cavity in the shape of an organism

• Mold fossil

• Preserved through freezing, amber, etc.

• True form fossil

• Organism turns to stone

• Trace fossil

• When a mold is filled in with minerals

• Cast fossil

• Shows an indication of life

• Petrified fossil

Fossils only form in what type of rock?

• Sedimentary

• Metamorphic

• Igneous

Which of these is an example of a trace fossil?

• A) Dinosaur footprint

• B) Petrified wood

• C) Amber with insect

• D) Shark tooth

What conditions are necessary for fossilization to occur?

• A) Rapid burial and hard body parts

• B) Exposure to sunlight and air

• C) High temperatures and pressure

• D) Presence of scavengers

Which type of rock is most likely to contain fossils?

• A) Sedimentary

• B) Igneous

• C) Metamorphic

• D) Volcanic

Tags

NGSS.MS-LS4-1