|How can a fossil provide evidence that a certain
|Question Date: 2017-01-19|
Good question. Scientists are always trying to
answer questions. Some questions might be:
• What animals used to live here?
• How have animals changed over time?
• Are the species we have here now been
here for a long time?
• How did this fossil get here?
• How do fossils form or get destroyed?
• How many things died that didn’t fossilize?
Some questions are about patterns in space, time,
or something else. Some questions are about
processes (how things happen).
Our EXPLANATIONS for patterns like finding clam
shell fossils on the top of a mountain are called
HYPOTHESES. How would you explain
shell fossils embedded in rock layers on the top
of a mountain? Here are a few hypotheses I
came up with:
• These are not really clam fossils, they
are rocks that just look like clam shells.
• These are weird land clams.
• This mountaintop was once covered with
• This mountaintop was once a giant meteor
that came from space that got its fossils from
As you read my list, some of these hypotheses may
have seemed more likely than others. Sometimes
weird hypotheses are correct. Often they aren’t.
We can never really PROVE how the clan
there, but some are consistent with
some are not. Scientists make predictions to help
analyze hypotheses. For example, we would say
something like, “If the mountaintop was once
covered with water, then we would predict that the
rock would be the kind formed at the bottom of a
sea or lake (sedimentary) and that we would find
fossils of other aquatic species in the same
layer. If our observations matched the prediction,
it would support our hypothesis, but wouldn’t
prove that it’s true. Maybe there’s a better
explanation out there that we haven’t thought of.
Notice that none of the hypotheses involved
supernatural causes like actions by
God/gods/spirits or magic. Science cannot say that
these things don’t exist, but supernatural
explanations cannot be evaluated by science
because they do not follow natural laws. They may
be valid hypotheses in some belief systems, but
they are not valid scientific hypotheses.
Back to your original question, let’s say I find a
fossilized bone (I wish!). I can tell it’s made of
minerals like silicon dioxide instead of calcium
and proteins like a bone would be by doing
chemical tests. How do I know it’s not just
I can look at its shape on a big scale or a small
one. Even on a microscopic level, it will still
have patterns like bone. How can I tell what
animal it came from? I can compare it to bones of
living animals or other fossils. This doesn’t
prove that it came from an animal that once
existed, but that would be the best explanation I
can think of. What would be your explanation?
Thanks for asking,
Thank you for the excellent question. Scientists
called paleontologists use fossils to study
organisms that lived in the ancient past. These
scientists are interested in discovering how long
ago different animals lived, how they survived in
their environment, and their evolutionary
There are two types of fossils, body
are the preserved remains of an organism’s body,
and trace fossils, which are things like the
footprints of ancient animals. Both types of
fossils provide evidence about the nature of
ancient types of life billions of years before
modern humans existed.
To understand how paleontologists use fossils to
make discoveries, first we need to learn about how
fossils are made. Sometimes animals get buried
under ground, for instance after a flood or
volcanic eruption. Over thousands of years the
minerals in the ground begin to replace different
parts of the animal’s body, in a process called
permineralization. Eventually, a rock is
place of where the animal used to be. This special
rock, or fossil, then provides lots of information
about what that animal was like.
With some knowledge about where to look and often
a bit of luck, paleontologists carefully dig up
fossils and often conduct experiments on them.
Studying fossils gives us direct evidence about
the size and shape, the anatomy, of an ancient
animal. Also, using radiometric dating
scientists can determine how old a fossil is,
which lets us know what types of animals were
alive during a certain time in the past.
All the known fossils make up the fossil record,
which is a history of the all the different things
to have ever lived on Earth. Patterns in the
fossil record provide evidence about the evolution
of life on Earth.
Thanks again for the fascinating question,
Great question. Most forms of life are preserved
as fossils, not just animals. Suppose we find a
fossil tooth in a sedimentary rock, and suppose
further that we can identify that tooth (elephant,
let's say), and we know how old that rock layer is
(30 million years, let's say), then we can be
pretty certain that that particular kind elephant
existed at that point in the past. There's really
no better way to account for why we find the
remains of ancient organisms in ancient rocks
other than to say those organisms existed in the
past. Some of those organisms might be pretty
similar to those still living (elephants, for
example), while others might be very different
(Triceratops, let's say).
When an animal dies, a fossil of the animal’s
bones may form if the conditions are right.
Paleontologists (scientists who study fossils) are
always discovering fossils that have never been
found before, providing support for a new animal
discovery! Paleontologists will use the bone
structure of fossils and compare them to previous
findings to figure out if a new animal has been
Here is a cool article about a recent dinosaur
article on fossils
This website talks about how most fossils are
formation of fossils
This is a great video that explains fossils:
If the fossil exists, then something had to make
that fossil, which means that at one time the
animal or plant that made it must have existed.
Thus by finding a fossil you are finding evidence
of something that once was.
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