Main content
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
© 2023 Khan AcademyTerms of usePrivacy PolicyCookie Notice
Barnum Brown: The man who discovered Tyrannosaurus rex
Known as the greatest dinosaur collector of all time, Barnum Brown helped the American Museum of Natural History establish its world-class fossil collection. Museum Research Associate Lowell Dingus and Chair of the Division of Paleontology Mark Norell recently traced Brown's extraordinary career from a frontier farm to the world's top fossil sites to the halls of the Museum in the book, Barnum Brown: The Man Who Discovered Tyrannosaurus Rex. Created by American Museum of Natural History.
Want to join the conversation?
Barnum was known as the "Known as the greatest dinosaur collector of all time"
How many dinosaur's did he collect in the period of his life?(6 votes)
Unfortunately, there is no real document on his Dino collection. I searched on the internet, but didn't get any information.
You could visit his wiki for more information :-http://en.wikipedia.org/wiki/Barnum_Brown(2 votes)
I noticed at2:34there was a 1905 newspaper headline that claimed the t rex specimen was thought to be 3 million years old. Was that the prevailing theory among scientists regarding the age of these fossils in Barnum's time or just a newspaper reporter's notion of old?(2 votes)
Interestingly, the first radiometric dating of rocks was carried out in 1905. The samples were predicted to be 92 to 570 million years old (later found to be 410 million to 2.2 billion years when the methods were refined). By the 1920s it was becoming apparent that the Earth was a few billion years old. However, it wasn't until the early 1930s that geologists began to take radiometric dating seriously.
Before that, Lord Kelvin's prediction that the Earth was 20 - 40 million years old was generally accepted. This was based on the cooling of the Earth. It wasn't until 1903 that radioactive decay was discovered which later was shown to challenge his calculation since it meant the Earth had an additional heat source he had been unaware of. There were other predictions based on sedimentation rates and salt deposition, which gave predictions between 3 million and 1.6 billion years old.
So it seems likely, that the newspaper headline was giving what was at the time, the scientific opinion. I don't know exactly how they came up with this number, but presumably it was based on the layers of rocks and predictions of how old each layer was.(1 vote)
- is there only one whole Skeleton of T-Rex ?
then were did the other T-Rex go ?
Did they jumped to the sea? :)(1 vote)
A quick look on Wikipedia says over fifty specimens have been found, several of which are quite complete skeletons, and a body ending up on a seabed improves its chances of being fossilised compared to staying on land.(2 votes)
how do they know exactly know where the fossils exactly are or if they could smell the bones.(1 vote)- Howdy,
The thing is, they don't know where the fossils are exactly. Paleontologists use geologic maps and other things of that nature to find the best location to find fossils and then they prospect, or start walking around that area, looking closely at the rock to see if they can find parts of exposed fossils. And, no Joshua, they cannot smell the fossils since over time dirt would take away it's smell. If it didn't than it just rot away.
Hope that helped!(1 vote)
- Are dilophosaurs real? if they are how big were they? srry if the name is spelled incorrectly(1 vote)
At2:33, it shows a thing from the past that says the specimen was 3,000,000 years old, which is false. What were dating methods used back then, and how do they compare to the accuracy of those today?(1 vote)- Interestingly, the first radiometric dating of rocks was carried out in 1905. The samples were predicted to be 92 to 570 million years old (later found to be 410 million to 2.2 billion years when the methods were refined). By the 1920s it was becoming apparent that the Earth was a few billion years old. However, it wasn't until the early 1930s that geologists began to take radiometric dating seriously.
Before that, Lord Kelvin's prediction that the Earth was 20 - 40 million years old was generally accepted. This was based on the cooling of the Earth. It wasn't until 1903 that radioactive decay was discovered which later was shown to challenge his calculation since it meant the Earth had an additional heat source he had been unaware of. There were other predictions based on sedimentation rates and salt deposition, which gave predictions between 3 million and 1.6 billion years old.
There's a good description of the various predictions and there problems here: http://abyss.uoregon.edu/~js/lectures/age_of_the_earth/age_of_the_earth.html
(The third section compares the different scientific predictions.)(1 vote)
How big was the biggest Tyrannosaurus rex that ever lived?(1 vote)
around 40-50'
6 tons(1 vote)
Did he ever find the first V-Raptor?(1 vote)- Who discovered the "Triceratops" and when?(1 vote)
- Triceratops was found by Mr. John Bell Hatcher in 1888, and named by Othniel Marsh in 1889.
Hope this answers you question! :)(1 vote)
2:34Video transcript
>>LOWELL DINGUS:
Barnum Brown was, by all accounts, the
best dinosaur collector who ever lived. He began his career here
at AMNH in 1897 going out on expeditions to
the American West first in search of fossil
mammals but of course later with the
dinosaur expeditions. He started as a field
assistant and worked his way up to be curator in the
Department of Vertebrate Paleontology, head of all
the dinosaur collections. >>MARK NORELL: The
majority of specimens that we have on display
were collected by him. I mean, he was the
one who collected the first Tyrannosaurus
Rex specimens. He was the one who collected
the Albertosaurus specimens. He was such a popular
and important guy during his lifetime
that he really, really, really kind of was the museum. >>SPEAKER: Curator Barnum
Brown found and brought back many dinosaurs. Here is the head of
dreaded Tyrannosaurus. The skeleton of a Pteranodon. >>DINGUS: We'd known for a
long time, both Mark and I, that there were 13
boxes of documents and correspondence up in the
archives of the Vertebrate Paleontology
Department and no one had ever written a comprehensive
biography of Barnum before. We felt like, given that
it was about a century after his discovery
of Tyrannosaurus, it was the right time
to celebrate his life. He happened to be born and
grow up during the first Bone Rush out into the American West
led by Othniel Marsh at Yale and his arch rival E.D.
Cope at the Philadelphia Academy of Sciences
beginning in the 1870s. >>NORELL: Barnum Brown collected
a number of Tyrannosaurus in the Hell Creek Formation
in the first decade of the 20th Century. A number of them
weren't that complete but they knew that there was
this big hypercarnivore which was out there. He found things like,
you know, a lower jaw, part of a brain case. Finally he found this specimen,
what would become the 5027 Specimen, and the
skull, which is still amongst the most beautiful
Tyrannosaurus skulls known, was found in one
single chert block. >>DINGUS: It was quite a
sensation right from the start. From the announcement
in the New York Times that they had discovered
Tyrannosaurus, there was a full page
article about the discovery, and that continued all
the way through until they unveiled the mount for the
public in the exhibition halls. >>NORELL: He would
go out on the road to give lectures and people
would flock around his trains when they came. He was one of the sort of
early sort of celebrity paleontologists in the sense
that he had his own CBS radio show each week which he
would talk about things. He was the Dinosaur
Consultant for Walt Disney and Shostakovitch for Fantasia. >>DINGUS: I don't think it's
too much to say that we all work in his shadow, especially
if you're working on dinosaurs. It's not only the fossils that
you're probably incorporating into your studies, no
matter what kind of dinosaur you're working on,
but he was also trained as a geologist at
the University of Kansas. And although he didn't take a
lot of detailed field notes, he had a very good eye for
the stratigraphy, the sequence of rock layers, in
the field area where he worked all over the world. No matter how hard you try,
especially here at the American Museum, you can never really
walk out of Barnum's shadow.