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Brachiosaurus

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The Brachiosaurus was a huge dinosaur that lived long ago.

Brachiosaurus altithorax side profile
Brachiosaurus altithorax side profile

It lived in North America during the Late Jurassic period. This was about 155.6 to 145.5 million years ago. It is a very famous animal in history. Many people know it from the movie Jurassic Park.

Altithorax
Altithorax

It was one of the first giants people ever imagined.

This dinosaur had a very special way it worked. Most long-necked dinosaurs have much longer back legs. Brachiosaurus was different because its front legs were longer.

Brachiosaurus Composite Skeletal
Brachiosaurus Composite Skeletal

This made its body slope upward like a hill. It had a very long neck and a small head. Because of this shape, it was a high browser. This means it could reach leaves high off the ground.

Brachiosaurus scale 1
Brachiosaurus scale 1

It could not stand up on its back legs like some others.

An American scientist named Elmer Riggs found the first bones.

Altithorax
Altithorax

He found them in 1900 near the Colorado River. The fossils were in a place called the Morrison Formation. Riggs worked with a crew from the Field Museum. They found a huge arm bone in a place called Quarry 13.

Brachiosaurus altithorax side profile
Brachiosaurus altithorax side profile

At first, Riggs thought the bone was a different kind of dinosaur. He only realized it was a Brachiosaurus after studying it in a lab.

There are many interesting facts about this animal. The name Brachiosaurus means "arm lizard" in Greek. The second part of its name means "deep chest."

Brachiosaurus sacrum ilium coracoid annotated
Brachiosaurus sacrum ilium coracoid annotated

This is because its chest was very wide and deep. The first specimen was found in western Colorado, United States.

Brachiosaurus leg bone
Brachiosaurus leg bone

Scientists once thought it was ectothermic, which means it needed the sun for heat. Now, many researchers think it was actually warm-blooded. This would help such a huge animal stay active.

We can see how this dinosaur links to things we know today. Its shape is a lot like a modern giraffe.

Even though it lived millions of years ago, it is still a star in science. You might see a plastic model of it at a museum or a theme park.

FMNH Brachiosaurus
FMNH Brachiosaurus

These models help us picture how big it really was. It remains a great example of the giant life that once walked our Earth.

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🖼️ Images & Media (28)
File:PSM V67 D572 Fossil bones of the great brachiosaurus altithorax.png
PSM V67 D572 Fossil bones of the great...
File:Brach humerus.jpg
Brach humerus.jpg
File:Altithorax.jpg
Altithorax.jpg
File:Brachiosaurus Composite Skeletal.svg
Brachiosaurus Composite Skeletal.svg
File:Brontosaurus skeleton 1880s.jpg
Brontosaurus skeleton 1880s.jpg
File:Ultrasauros scapulocoracoid 2.jpg
Ultrasauros scapulocoracoid 2.jpg
File:Brachiosaurus leg bone.jpg
Brachiosaurus leg bone.jpg
File:Museum für Naturkunde (36556352434).jpg
Museum für Naturkunde (36556352434).jpg
File:Brachiosaurus composite Matthew 1915.jpg
Brachiosaurus composite Matthew 1915.jpg
File:Lusotitan mid caudals.png
Lusotitan mid caudals.png
File:Brachiosaurus nougaredi Sacrum.png
Brachiosaurus nougaredi Sacrum.png
File:Brachiosaurus_scale_1.svg
Brachiosaurus_scale_1.svg

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