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Chirostenotes

A bird-like dinosaur with a toothless beak

WWD - Prehistoric Planet

Chirostenotes was a bird-like dinosaur with a toothless beak, slender claws and long, powerful legs.

They call it home

Chirostenotes lived alongside Euoplocephalus in a landscape of fast-flowing rivers and forests.

What we heard about their hearing

What we heard about their hearing

Chirostenotes is thought to have heard low frequency sounds just like birds today.



What big teeth you have

What big teeth you have

Chirostenotes did not have teeth. Instead it had a toothless beak, just like a bird.



Nose knowledge

Nose knowledge

Although many theropod dinosaurs had a well developed sense of smell, oviraptorosaurs like Chirostenotes seem to have lacked this due to their more herbivorous/omnivorous diet.

The most fantastic find

The most fantastic find

The discovery of Chirostenotes has been quite a long-winded affair. The first fossils to be uncovered – by George Sternberg in 1914 – were the animal's hands. A few years later, its feet were discovered, though these were mistakenly attributed to another dinosaur, Macrophalangia. Chirostenotes' jaws were found a few years after that and attributed to Caenagnathus. Then in 1988, Philip Currie and Dale Russell found a specimen in storage which helped link all the previous discoveries together as fossils of Chirostenotes.

Chirostenotes features

Chirostenotes features Height: 1.5m (4.92ft)
Length: 4m (13.12ft)
Weight: 99.79kg (220lbs)
Top speed: 60kph (37.3mph)
Vision: Theropods are thought to have had excellent vision. Chirostenotes had large eye sockets and a bird-like brain, hinting at particularly sharp vision.
Skin: Chirostenotes had feathers, which are likely to have been concentrated around their tails and arms. These would have been used for brooding young and displaying to mates or competitors.
Brain: Chirostenotes was closely related to birds and would have shared their complex behaviour. They would have been some of the more intelligent dinosaurs.
Prey: With a toothless beak, gastroliths (possibly) in its gut and sharp predatory claws, it is likely Chirostenotes ate a mixture of different foods, including small reptiles, mammals, plants, eggs and insects.
Bite: Chirostenotes had no teeth. Instead it had a beak and an elongated second finger, which some scientists believe was used to probe for grubs and armoured amphibians.
Nest: Oviraptorosaurs like Chirostenotes laid eggs in nests. They laid their oval eggs in pairs with the more pointed end orientated towards the centre of the nest.

Chirostenotes facts and theories

Chirostenotes facts and theories

  1. Oviraptorosaurs like Chirostenotes look a lot like birds. They had feathers, beaks, and short tails. But they are not very closely related to birds. Instead, dinosaurs like Velociraptor are much closer cousins to birds. The similarities between Chirostenotes and birds result from convergent evolution: when distantly related animals evolve similar features because they have similar lifestyles or diets.
  2. Chirostenotes was an oviraptorosaur. These were feathered bird-like dinosaurs that were common in the Cretaceous Period. They belonged to the theropods, a wider group of bipedal, mostly carnivorous dinosaurs which also included Tyrannosaurus rex.
  3. Fossils have been found of Chirostenotes' closest relatives in the act of brooding their young in a nest, just like modern birds do. They can be seen arranging their eggs in such a way as to completely shelter them with their feathered arms.
  4. Oviraptorosaurs may have shaken their tail feathers just like a peacock. Palaeontologists have found that their tail was short and covered in feathers, but with major muscles in the tail for fast movements. If this is correct, it's highly likely that their feathers were very colourful!
  5. Chirostenotes had a parrot-like skull with a bony crest. These were formed from enlarged nasal bones, with the nasal openings positioned in an unusual place above the eyes and behind the beak.