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Troodon

One of the most intelligent dinosaurs discovered so far

WWD - Prehistoric Planet

Troodon was a small bird-like dinosaur with long, slender hindlimbs. It had grasping hands and two large retractable claws on the second toe of each foot.

They call it home

Troodon lived among the streams and deltas of coastal plains on the island continent of Larimidia alongside Euoplocephalus, Dromaeosaurus and Nanuqsaurus.

What we heard about their hearing

What we heard about their hearing

The braincase of Troodon shows a well developed sense of hearing.



What big teeth you have

What big teeth you have

Troodon teeth are serrated – a feature often seen in animals eating a significant amount of plant food. Troodon is therefore thought to have been omnivorous.


Nose knowledge

Nose knowledge

We know that Troodon had a better sense of smell than modern-day birds, but a worse sense of smell than crocodiles and larger theropod dinosaurs like Tyrannosaurus rex.

The most fantastic find

The most fantastic find

In 1983, Jack Horner uncovered dinosaur eggs and nests within the Two Medicine Formation (a strip of rock dated to the Late Cretaceous period) in Montana. Horner, along with fellow palaeontologist David Varrichio, described a partial skeleton of an adult Troodon brooding a clutch of at least five eggs, just like a bird.

Troodon features

Troodon features Height: 1m (3.28ft)
Length: 2.4m (7.87ft)
Weight: 49.9kg (110lbs)
Top speed: 39kph (24.23mph)
Vision: Troodon had huge eyes which would have enabled it to hunt at night or during the long, dark polar winters.
Skin: Troodon comes from a lineage of dinosaurs that had feathers. Most scientists hypothesise that Troodon would have had them too.
Brain: Troodon is thought to be the most intelligent dinosaur discovered so far. Its EQ or encephalisation quotient (a measure of brain size compared to body size) was six times higher than the dinosaur average.
Prey: There is a possibility that Troodon hunted in packs. If this were the case, they could have taken down much larger prey than would have been possible individually. However, we have no real evidence of pack behaviour as yet.
Bite: The teeth of Troodon are serrated, which is often a characteristic of herbivores. But because Troodon runs fast, has excellent stereoscopic vision, grasping hands and sharp claws, it is thought to have been carnivorous. Some palaeontologists believe it might have been omnivorous.
Nest: Troodon nests were built from sediment and were about 1m (3ft) in diameter with a pronounced rim. There would have been about 20 eggs in each nest.

Troodon facts and theories

Troodon facts and theories

  1. Troodontids are closely related to the dromaeosaurids, the group that includes Velociraptor. Together, members of the troodontid and dromaeosaurid group are the closest cousins to birds among all theropods.
  2. Troodon is a member of the small-to-medium-sized bird-like theropod dinosaurs known as the Troodontidae. They were a member of the coelurosaurian clade, which included all those theropod dinosaurs more closely related to living birds than to Allosaurus.
  3. Troodon definitely built a nest, laid its eggs and incubated them in a bird-like manner. The male would have been the one to sit on the nest, as in many modern birds today.
  4. Some Troodon fossils are found far north in Alaska, which would have been positioned within the Arctic Circle during the Cretaceous. It is thought Troodon was well adapted for enduring long polar winters.
  5. Troodon's two large retractable sickle-claws were raised off the ground while it ran at speed.
  6. Troodon's eyes faced forwards which would have given it excellent stereoscopic vision and depth perception - essential when hunting.
  7. If Troodon was an omnivore as some scientists hypothesise, it probably fed on small lizards, mammals, invertebrates and plant material.