3rd Grade Ch. 2 Lesson 4 How are animals from the past like today's animals

Ch. 2 Lesson 4How are

animals from the past like

today’s animals?

fossils• signs of past life• made from hard

parts of animals• tell how Earth has

changed over time

1. fossil mold• space in the shape of an

animal in rock

2. cast• shape of

original fossil• fossil mold that has

been filled with rock materials over time

3. amber• hardened

tree sap that traps animals

4. fossils in tar pits1. Animals fell into tar pits2. Soft parts of animals broke down3. Left actual bones behind

Saber-toothed tiger

Unlike the fossil remains of mostdinosaur bones, the bones of

this fossil saber-toothed tiger areactual bone.

extinct• no longer living

Badlands in South DakotaBefore

hot, wet climate

After

desert

Reptiles resemble dinosaurs

What is hardened tree sap that trapped animals?

tarambercastfossil mold

The Badlands in South Dakota have always been a desert.

TRUE

FALSE

fossil moldcastambertar pit

What kind of fossil is this?