>>AKI WATANABE (paleontologist, AMNH & NYIT):
How do you find dinosaur fossils?
[MUSIC] [BOOM]
>>WATANABE: Discovering a dinosaur fossil
is one of the most exciting parts of being
a paleontologist.
But it also takes a lot of preparation
and hard work.
So the first step is for the paleontologist
to figure out where to dig for fossils.
The region has to include sedimentary rock
layers, like limestone or sandstone because
those are the rocks that contain fossils.
These sedimentary rock layers need to be exposed
on the surface so that the fossil bones are
on the ground where paleontologists could
easily pick them out.
The sedimentary rock layers need to have been
formed while dinosaurs were alive, so that
would be between about 
230-66 million years ago.
So if a region ticks all these three boxes,
then there's a good chance that you'll find
some dinosaur bones in the area.
So once you've made the decision on where
to look for fossils, then it's time to actually
start your fieldwork.
The first phase is called prospecting where
all of us would just stare at the ground for
miles and miles and hours and hours until
we find fragments of bone on the ground.
And we walk with this magnificent tool called
the rock hammer, so when we do find fragments
of bone sticking out of the ground, then we
can use it to either take it out of the ground
and also to dig a little further to see if
there are any other bones nearby.
A lot of people might think that when you're
looking for fossils you might see whole skeletons
but typically what you find are fragments
and very damaged pieces of bone
like this one here.
So one of the important skills for paleontologists
is to be able to tell apart fossil bone from
regular rocks.
And so we look for features like grain texture
on the surface and also internally there should
be holes where blood vessels and bone cells
used to be.
Paleontologists can learn a lot from just
little bits of bone.
We can learn about how the dinosaur grew,
or what the overall size was, and in a lot
of cases, we can tell to which group these
fossils belonged to.
So this is a piece of bone from
a duck-billed dinosaur.
Once you find some dinosaur fossils then you're
ready to move on to the next phase of fieldwork
which is called excavation.
And this is where you dig out the fossil bones.
But at this point you are not interested in
taking out the bones individually because
a lot of the fossil bones will be fragile.
You'll be taking out the bones with the surrounding
sediment and then shipping it to a lab so
that you can prepare it using
specialized tools.
So the steps involved in fieldwork hasn't
really changed in over a century although
a lot of the techniques for analyzing dinosaur
bones have changed quite a bit, even in the
last decade.
And finding fossils still takes dedication
and determination, a little bit of luck, and
also knowing what to look for.
Right now there are paleontologists digging
up dinosaur bones on all seven continents.
And so this might make some people worry that
there will be a shortage of dinosaur fossils
in the future.
But we’re finding more and more fossils,
and there’s no sign of it slowing down.
For me it’s the best part of being a dinosaur
paleontologist.
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