GRADE 5
Name:
Fossils are the remains of ancient plants and animals that lived thousands of years
ago, that have been preserved in layers of rock. They are important to us because
they provide us with a picture of what life was like thousands of years ago. These
organisms are now extinct because their species have died out. The only way we
know they existed in the past is because we have their fossils.
Where can fossils be found?
Not every type of rock contains fossils. Most fossils are found in sedimentary rock.
This rock is formed when layers of eroded earth are deposited on top of each other.
These layers are pressed down more and more through time, until the bottom layers
slowly turn into rock. The process by which sedimentary rocks are formed is delicate
enough that fossils can be preserved within them.
How were fossils formed?
Fossils were made when living things died and got buried quickly before the hardest
parts of the animal had a chance to decay. Over thousands of years, more and more
layers of sand and mud settled on top of the animal. All these layers caused pressure
which made the skeleton harden into rock. This is the process of fossilisation. Over
time, the rock surrounding the fossilised skeleton is eroded by wind and water. When
the fossil is close enough to the surface, it may be dug up by scientists. If all the
bones are found, the whole skeleton can be rebuilt.
Activity 1: Fossilisation
1
Match the following descriptions to the pictures on the left by
writing the number of the correct picture under the correct
description.
• Over thousands of years, the rock is eroded by wind and water to expose the fossil.
2
• A dinosaur dies and the soft parts of its body decay.
3
• Over thousands of years the many layers of mud covering the skeleton turns to rock.
4
• The skeleton is covered by sand and mud before it can decay.
© e-classroom 2014 www.e-classroom.co.za
Grade 5 Term 4 Natural Science and Technology: Planet Earth and Beyond and Systems and Control: Fossils in Rock
Fossils in rock
GRADE 5
Paleontologists are people who study plants and creatures that lived thousands of
years ago. Because they study life forms that are now extinct, they rely on fossils to
learn about life in the past. By examining an extinct animal’s skeleton, we can tell
what the animal looked like, how big it was, how it moved, what kind of food it ate
and how long ago it lived.
Activity 2: Imagine you are a
paleontologist
You have just found the bones below. Cut them out
and try to put them together to make a skeleton.
© e-classroom 2014 www.e-classroom.co.za
Grade 5 Term 4 Natural Science and Technology: Planet Earth and Beyond and Systems and Control: Fossils in Rock
People who study fossils
GRADE 5
Activity 1: Fossilisation
Match the following descriptions to the pictures on the left by writing the number of
the correct picture next to each description.
• Over thousands of years, the rock is eroded by wind and water to expose the fossil.
4
• A dinosaur dies and the soft parts of its body decay.
1
• Over thousands of years the many layers of mud covering the skeleton turns to rock.
3
• The skeleton is covered by sand and mud before it can decay.
2
© e-classroom 2014 www.e-classroom.co.za
Grade 5 Term 4 Natural Science and Technology: Planet Earth and Beyond and Systems and Control: Fossils in Rock
Answer sheet