Fossil Facts

Fossils are the remains of plants and animals that were once living. They are the remains of extinct organisms such as animals and plants that are no longer living on our planet. Bones, shells, leaves, and feathers can all become fossils.

Fossil Facts for Kids:

  • Fossils are the remnants of plants and animals that lived long ago.
  • Paleontology is the study of fossils
  • The oldest fossils discovered by scientists are 3.48 billion years old
  • The World’s biggest T. rex was discovered in Canada in 2019
  • The first dinosaur fossil was discovered in 1819 and later called Megalosaurus
  • A three-year-old boy was the youngest person to ever find a fossil.  He lived in New Mexico.
  • In Utah, there is a Dinosaur Quarry.  This Dinosaur Quarry has had hundreds of bones from different dinosaurs.
  • Stony fossils take millions of years to form.
  • When an animal in the ocean dies, its only chance to be a fossil is if it isn’t eaten by another animal.
  • When the soft parts of the body decay, the bones are replaced by minerals from water that flows through and leaves sand and mud in its place.
  • When a fossil turns into rock, this is caused by all of the pressure of the different layers surrounding the fossil.
  • The Coelacanth is a fish that is over 360 million years old.  This fish is sometimes called a “living fossil.”
  • A living fossil is a fossil that is alive today but that had also existed millions of years ago.  The fossils prove how long it has been around.
  • When something looks like a fossil, but it isn’t, it is called a pseudo fossil.
  • Scientists use the footprints of animals to tell how fast they ran or how many legs they had.  These footprints can also tell if the animals lived alone or in groups.
  • Some rocks are called gastroliths and these are rocks that have been swallowed by dinosaurs to help them digest the food that they eat.
  • The skeletons of whole dinosaurs have been recreated because of fossils that have been found in the Earth.

Types of Fossils

Even though there are different types of fossils, there are two main types of fossils.

  • Trace Fossils
  • Body Fossils

Trace Fossils

Trace fossils are fossils that show that there was once the thing living.  An example of a trace fossil is the footprint of a dinosaur.  The footprint is a sign that the dinosaur biological activity.

Body Fossils

A body fossil is a fossil that is the remains of a plant or animal that once was alive and living.  A great example of a body fossil are Dinosaur bones such as a skull.

What is Paleontology?

Body fossil

When a scientist studies fossil, they are called a paleontologist.

They study plants and animals that lived millions of years ago and check fossil records for undiscovered. They have many surprising discoveries about life on Earth before man. Different Dinosaur species dating back to the Triassic, Jurassic, and Cretaceous periods.

They look for fossils in the field, spending time digging and collecting them from all over the world.

Scientists continue to discover new species

What Types of Tools Do Paleontologist Use?

Paleontologists use different types of tools to dig for fossils such as:

  • Hammers
  • Chisels
  • Saws
  • X-rays
  • Trays
  • Knives

What Does the Word Fossil Mean?

The word fossil comes from the Latin word “fossils.”  The Latin word “fossils” means “dug up.”

The reason that this word means dug up is that most of the fossils that are found are dug out of rocks, mostly sedimentary rocks.

How Are Fossils Formed?

Fossil of a Seymouria

They are formed when there are small pieces of dirt, rock, and debris that are pressed together over time.

The fossils become buried deeper and deeper into the Earth as more rock layers pile on top of it.  Soon, the fossils are pressed together, and they form sedimentary rocks.

Sedimentary rock is a rock that is formed from things such as sand, mud, and little tiny pieces of rocks.

When a fossil is formed, there is not a bone in it.  The fossil looks like the animal or plant that it is from, but it is made up of rock and not bone.

Natural Disasters

Sometimes, animals are buried quickly by natural disasters such as volcanoes or sandstorms.

When this happens, the animal is covered by other sediments.  Some of the animals will then decay while other parts of it stay in the same shape it was when it died.  This is when parts of the animal will turn into fossils as time goes by.

As the animal stays buried, the body will have chemical reactions, and this will cause the bone and the rest of the body to decay.  When this happens, rock is replaced in the spot where the animal was, and this is called fossilization.

Fossilization happens when the original part of the plant or animal dissolves and is replaced by other minerals.

When we find fossils, it is just a copy of the animal.  It is the same shape and the same form of the plant or animal, but it is made up of rock and not part of the plant or animal.

Stone Fossils

A stone fossil is a fossil that is similar to mold.

When an animal dies, its body gets eaten and it leaves behind its bones.  The sand and mud will then cover the bones.

Years later, the bones slowly wash away, and it leaves the shape of the original animal.  The specimen soon becomes rock, and this is what a mold fossil looks like.

Whole Animal Fossil

Sometimes, paleontologists will get lucky and they will find the full skeleton of an animal that existed many years ago.

One example is the Wooly Mammoth.  If a Wooly Mammoth gets trapped in ice for years and years, the animal is preserved, and it does not change.

Insects can get stuck in Amber or tree sap and they look like they did right when they entered into the sap.

Vertebrate Fossils – Vertebrates are animals with backbones. This would include mammals, birds, fish, reptiles, birds, fish, and amphibians.


When something is hard and replaced with organic material such as pyrite or silica, this is called petrification.  When wood is very old, it is sometimes petrified wood.

When an insect gets stuck in Amber, it is also petrified.  Amber is a type of tree sap that makes rock hard and is usually see-through.

When a scientist finds a footprint from an animal or dinosaur, the footprint is usually an impression or a print from the animal.  This print is usually filled with different sediments and they get hard and they keep the footprint the way that it was when the animal made it.


When all of the organism is dissolved except for the carbon, the carbon leaves an outline of the organism.  This is called carbonization fossils.


When an area is really dry, it can cause there to be a mummified fossil.  This happens when the organism dies and dries out fast because there is no moisture.


When a fossil is formed from different materials such as silicate, pyrite, and carbonate, they form a cast and this makes a fossil.

How Many Animals are Fossilized?

Even though there is no exact count of how many animals are fossilized, there are many that are and many that aren’t.

Some animals just decayed, and they never were fossilized.

It helps scientists reconstruct the evolutionary stages of organisms that but they believe that this is only a small percentage of dinosaurs that formed into fossils. Because of mass extinction, many others that lived during the Dinosaur Ages never fossilized.

Where Are Fossils Found?

The wasp trapped in Dominican amber

Fossils are found in many different places, all over the world.  Some fossils are exposed to erosion such as water erosion or wind erosion and are then discovered of the surface.

Sometimes paleontologists do not even have to dig down to find these fossils.

Close to Water

Some fossils are found close to rivers and lakes or the ocean.  This happens because water mixes with the sediments to form mud and silt that gets very hard as time goes by.  Scientists can then find the fossils close to water.

Inside Ice

Some animals have been found preserved or unchanged in ice.  Even human remains were found in 1991 in Italy.

Inside a Forest

Inside of forests is the place that many insects and tree fossils exist.  Some animals and insects can get trapped in sap while trees can be found especially in old forests.

What Do Fossils Teach Us?

Fossils are important because they help to teach us about animals, plants, and even humans that lived many, many years ago.  If we did not find fossils, we would never know that dinosaurs or Wooly Mammoths existed.

What Did You Learn?

  • What is a fossil?  A fossil is the remains of an animal, plant, person, or insect that has been preserved or saved.
  • Why is studying fossils important?  Studying fossils can help people to be able to learn more about the past.  They can help to learn about animals, plants, insects and even people that lived millions of years ago.
  • What is someone that studies fossils called?  A person that studies fossils is called a paleontologist.
  • What are the two main types of fossils?  The two main types of fossils are body fossils and trace fossils.  Body fossils are fossils that take shape from the body of an animal, plant, insect, or person that has died and a trace fossil is a fossil that proves that something lived in the past.
  • What are some types of animals that have been turned into fossils?  Dinosaurs, Wooly Mammoths, and many plants and insects have been found in the form of fossils.