What animals can you name that went extinct before you were born?

Question

We can learn about these animals through the fossils they have left
behind.
EXPLORE
The fossil record includes all of the known fossils that
document the history of life. We learn about the past by
studying the remains of things that lived many years ago.
Explanation
The first animals likely lived on Earth about 800 million
years ago. Crazy to think about, right? Here’s another
interesting fact—99.9 percent of species that have lived on
Earth over time are now extinct. How can scientists give us
detailed facts about these extinct animals that lived
hundreds, thousands or even millions of years ago? The
answer is found in the fossil record.
Fossils are preserved remains or traces of organisms that
lived in the past. Even though millions of animals have lived
and died on the Earth in its history, fossils are very rare
because most parts of organisms decompose quickly after death. Most of the time fossils preserve
only the hard body parts like bones and teeth. For fossilization to take place, usually the remains
need to be covered by sediment right away after death. Other fossils result from remains freezing,
Fossil of a bat
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drying, being trapped in amber, or being buried in oxygen-free environments. There are other
trace fossils that preserve other evidence of animals like burrows, droppings, footprints, nests,
eggs. All of the many varied fossil types that have been
collected over time comprise the fossil record, which tells
the history of life on Earth.
Paleontologists can determine when a specific animal lived
by dating the fossils. They use two methods to do this. The
first is to determine a fossil’s relative age by examining its
position within a sedimentary column of rock. The relative
age is defined as the approximate geologic age of a fossil,
rock, or geologic feature or event. The closer the fossil is to
the surface, the younger it is. Paleontologists worldwide
have been able to create a geologic time scale for the Earth
based on information gathered about the relative position
and composition of fossils. Scientists can also use
radiocarbon dating to date fossils that are younger than
around 50,000 years old. . Radiometric dating can be
used to find the age of a fossil based on the half-lives
of decaying radioactive materials found within it.
The fossil record gives information about how animal
groups have changed, adapted, and evolved over
time. It helps explain vestigial structures, which are
cells, tissues, and organs in animal and human bodies
that no longer serve a purpose. The study of how
organisms develop is called embryology. The fossil
record helps scientists piece together the history of
life on Earth even millions of years before the written
historical record. The fossil record also gives
information about the climate and environment of
specific places and points in time.
EXTEND
The most obvious place to go to see fossils is a history museum, but some fossils can also
be found in nature. The most common of these, perhaps, is shells found on the beach
and in the ocean. Other examples are petrified wood, coal, oil, teeth, and bones.
Research your specific area to see what kinds of fossils have been discovered.
All shells on the beach are fossils
Fossil preserved in amber
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Fossil Record
Complete the sections below with information from the article.
Vocabulary
Write the definition of each concept.
Definition
Fossil Record
Organisms
Fossilization
Application
The most obvious place to go to see fossils is a history museum, but some fossils can also be found
in nature. The most common of these, perhaps, is shells found on the beach and in the ocean.
Other examples are petrified wood, coal, oil, teeth, and bones. Research your specific area to see
what kinds of fossils have been discovered.
© Clark Creative Education
FOSSIL RECORD
About 99.9 percent of species that have lived on Earth over time are now
extinct. How do we know about these extinct animals that lived hundreds,
thousands or even millions of years ago? The answer is found in the fossil
record. Fossils are preserved remains or traces of organisms that lived in
the past.
Even though millions of animals have lived and died on the Earth in its
history, fossils are very rare because most parts of organisms decompose
quickly after death. Most of the time fossils preserve only the hard body
parts like bones and teeth. All of the many varied fossil types that have
been collected over time comprise the fossil
record, which tells the history of life on Earth.
The fossil record gives information about how
animal groups have changed, adapted, and
evolved over time. It helps explain vestigial
structures, which are cells, tissues, and organs in
animal and human bodies that no longer serve a
purpose. The fossil record also gives information
about the climate and environment of specific
places and points in time. Scientists can determine the relative age of a
fossil through radiometric dating or by looking at the fossil’s position in a
column of rock

Answer 1

Vocabulary

Fossil Record: The fossil record refers to the totality of fossils that have been discovered and documented, providing a historical account of the development and evolution of life on Earth over time.

Organisms: Organisms are living entities that can function independently, including animals, plants, fungi, and microorganisms.

Fossilization: Fossilization is the process through which the remains or traces of organisms are preserved, often involving the rapid burial of remains in sediment or other conditions that prevent decomposition.

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FOSSIL RECORD Application

About 99.9 percent of species that have lived on Earth over time are now extinct. The fossil record serves as the primary source of information about these extinct animals that existed hundreds, thousands, or even millions of years ago. Fossils, which are the preserved remains or traces of past organisms, are rare due to the quick decomposition of most living parts after death. Typically, fossils only preserve hard body parts like bones and teeth.

The fossil record is invaluable as it reveals how animal groups have changed, adapted, and evolved over time. It also explains the presence of vestigial structures in living beings—these are organs or tissues that have lost their original function. Furthermore, the fossil record informs scientists about historical climate and environmental conditions, allowing them to piece together the Earth’s biological and ecological history over various geologic time periods. Scientists determine the age of fossils through methods such as radiometric dating or by examining the fossil's position in a sedimentary column of rock.