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American Museum of Natural History
Course: American Museum of Natural History > Unit 1
Lesson 4: Dinosaur fossils- Fossil preparation
- What Is a fossil?
- How do we know where to look for dinosaur fossils?
- How do we know where to look for dinosaur fossils?
- How are dinosaur fossils discovered and collected?
- How are dinosaur fossils discovered and collected?
- How are dinosaur fossils prepared in the laboratory?
- How are dinosaur fossils prepared in the laboratory?
- Preparing dinosaur fossils
- Inside the Collections: Paleontology and the Big Bone Room
- Can we clone extinct dinosaurs from DNA preserved in their fossils?
- Can we clone dinosaurs from DNA?
- Barnum Brown: The man who discovered Tyrannosaurus rex
- Quiz: Dinosaur Fossils
- Exploration Questions: Dinosaur Fossils
- Answers to Exploration Questions: Dinosaur Fossils
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Preparing dinosaur fossils
Fossil preparators are highly skilled technicians who restore the naturally fractured bones and teeth of fossil to the original state, somewhat like art conservators restore damaged paintings and sculptures.
When fossils arrive from the field, they are encased in plaster jackets and the rock, or matrix, which was deposited around the fossils. Fossil preparation involves cutting open the plaster jacket and removing this matrix surrounding the fossil. Created by American Museum of Natural History.
When fossils arrive from the field, they are encased in plaster jackets and the rock, or matrix, which was deposited around the fossils. Fossil preparation involves cutting open the plaster jacket and removing this matrix surrounding the fossil. Created by American Museum of Natural History.
Want to join the conversation?
- How does one become a fossil preparator?(3 votes)
- They most likely also need to know the distinct feature between those to elements so they don't chisel off anything valuable.(2 votes)
- how do they know what is rock and what is fossils(1 vote)
- The fossils are made out of bones and are easily distinctive from rocks.(2 votes)
- Is the dinosour bones and bodys every where in the world ?(1 vote)
- Yes, Dinosaur bones have been found on every continent, even antartica.(1 vote)
- Is there a way to determine if scattered bones come from a single dinosaur? Could DNA samples be taken from fossilized teeth, claws, and bones?(1 vote)
- Could you scan a fossil and print it with a 3D/printer?(1 vote)
- Why do they cover all the holes in the t-rex dinosaur skull?(1 vote)
- Because when they found it, it was already filled with minerals, it takes a very long time to clean it out, so they are probably still working on the one in the video. Hope this helps!(1 vote)
Video transcript
>>JUSTY ALICEA: This, specifically, is
the skull of a dinosaur from a group of families called Ankylosaurs. They are the
armored dinosaurs. If you could imagine an armadillo with a lot of spikes all over it. It's
a common misconception that bones are dug in the field where they're found. What actually happens
is that a researcher will be walking through, you know, deserted, barren canyon land looking for
bones sticking out of the rocks or weathering out. A trench is dug around the the specimen. Then
it is wrapped in bandages soaked in plaster, which is what you see here. So, this is straight
from the field where it was found in Mongolia. For this kind of material, I would use small tools,
like these needles and things like that, and some brushes to slowly work off the rock from the bone.
This is soft enough where I can use these kind of needles and things like that to kind
of gently work it off. We're basically chipping away till we get to the surface of
the bone and then what we're doing from there is following the line of the bone around,
gradually removing the rock as we're doing so. So, what I'm doing is essentially just using
this needle to softly work off the surface of the rock until I get to the layer of
bone underneath. I've been working on this piece already about five months already. And
it's probably going to take me another three or four to get it to the condition that
the researchers want it in. Every year, these researchers go out to the field and collect
hundreds of specimens and they bring them back here to the Museum. A lot of times we just find
pieces like you see here. These are just broken pieces of bones of individual dinosaurs and
things like that. But once in a while we do get whole dinosaurs and this tells us very much
about the anatomy. This is how we know how certain dinosaurs were, actually how their
bones were arranged and things like that. Using a silicone rubber we've actually made a mold
of the skull here. And then filling it in with an epoxy resin we basically make a copy of the skull.
You can see here. And this is research quality. You can take this under a CT scanner and it will
literally have all of the folds and wrinkles and cracks of the original specimen. We'll take
about four copies of each bone that we do. One scientific quality cast, another
one for the home institution. So, whatever country we've gotten it from,
they'll get a copy of it, as well. Somebody will sit here and literally block
out these pieces, put them back together and then mold the whole thing all together
and get this this cast that you see here.