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Deinonychus

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Deinonychus was a very special kind of dinosaur.

Deinonychus ewilloughby
Deinonychus ewilloughby

It was a dromaeosaurid, which is a group of meat-eating dinosaurs. This animal lived a long time ago during the Early and Late Cretaceous Period. That was about 115 to 93.9 million years ago. It was an active and agile predator.

Deinonychus (Raptor Prey Restraint)
Deinonychus (Raptor Prey Restraint)

Many people used to think all dinosaurs were slow and heavy. The discovery of Deinonychus changed that idea forever. It showed that some dinosaurs were fast and smart hunters.

This dinosaur had a very interesting way of moving. It had a sleek body and a horizontal posture. Its tail was very important for balance. The tail had stiff tendons that helped it act as a counterbalance. This kept the animal steady as it ran.

Deinonychus patte arrière gauche
Deinonychus patte arrière gauche

It also had a very famous feature on its feet. Each hind foot had a large, sickle-shaped claw on the second toe. This is called a raptorial claw. It likely helped the dinosaur catch its prey.

Scientists have been studying these fossils for a long time. The first remains were found in 1931 near Billings, Montana. A paleontologist named Barnum Brown found them while looking for other fossils. Later, in 1964, John Ostrom led a big expedition.

Deinonychus antirrhopus hand
Deinonychus antirrhopus hand

His team found over 1,000 bones from at least three different animals. Ostrom's work was very important for science. He officially named the species Deinonychus antirrhopus in 1969. His studies helped start what people call the "dinosaur renaissance."

There are many cool facts about how this animal lived.

Deinonychus skull ROM
Deinonychus skull ROM

Fossils have been found in Montana, Utah, Wyoming, and Oklahoma. Some teeth were even found in Maryland. A fully grown Deinonychus could be quite large. One estimate says it could reach a certain length and weigh a specific amount. Scientists also found fossilized eggshells near some bones. This suggests the dinosaur might have sat on its eggs to keep them warm. This is a way to use body heat to help eggs grow.

Deinonychus helps us understand how birds and dinosaurs are linked.

Archaeo-deinony hands
Archaeo-deinony hands

John Ostrom noticed that the arms of Deinonychus looked like the arms of birds. Because of this, many scientists now believe birds came from dinosaurs. We also think Deinonychus might have had feathers. Other related dinosaurs like Velociraptor have clear evidence of feathers. Even though we have not found skin impressions for Deinonychus, it is a very likely guess. It was much more like a bird than a slow reptile.

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🖼️ Images & Media (32)
File:Deinonychus patte arrière gauche.jpg
Deinonychus patte arrière gauche.jpg
File:Harvard Deinonychus.jpg
Harvard Deinonychus.jpg
File:Deinonychus antirrhopus - AMNH - DSC06297.JPG
Deinonychus antirrhopus - AMNH - DSC06297.JPG
File:Archaeo-deinony hands.svg
Archaeo-deinony hands.svg
File:Dromaeosaurs.png
Dromaeosaurs.png
File:Austroraptor Restoration.png
Austroraptor Restoration.png
File:Changyuraptor.png
Changyuraptor.png
File:Bambiraptor reconstruction.jpg
Bambiraptor reconstruction.jpg
File:Adasaurus Restoration.jpg
Adasaurus Restoration.jpg
File:Tsaagan.png
Tsaagan.png
File:Saurornitholestes langstoni skeletal.png
Saurornitholestes langstoni skeletal.png
File:Fred Wierum Velociraptor.png
Fred Wierum Velociraptor.png

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