card
043

Troodontid nest

OLogy Series
specimen
card
043

Troodontid nest

OLogy Series
specimen

About 80 million years ago in the Gobi Desert, sixteen dinosaurs hatched in this nest. One of the hatchlings died before it left the nest. Bad news for the hatchling, but good news for scientists. This evidence tells us that this nest once contained troodontid dinosaurs.

How Smart Were Troodontids?
Compared to their body size, some troodontids had the largest brains of any non-bird dinosaurs. Did this mean they were the most intelligent? Maybe. But measuring the intelligence of extinct animals based on fossils can be risky. For example, even though the closest relative to humans, Neanderthals, had a bigger brain that we do, it seems unlikely that these cave people were very smart. Using fossil evidence, paleontologists guess that troodontids were probably as smart as primitive modern birds such as rheas or ostriches.

Scientists found each egg standing on its end. What is the best explanation for this position?

A sandstorm blew the eggs into this position.

A troodontid adult put them in this position millions of years ago.

When the nest became fossilized, the eggs shifted upward.

Are you right?

Correct!

This specimen gives us clues about how troodontid parents may have laid their eggs.

Roy Chapman Andrews

These (troodontid) dinosaurs are much too late in geological time to be ancestral to birds, but they do parallel them remarkably...

Amy Davidson

...I used a hard carbide needle to remove rock from the troodontid skull. I wanted to expose the imprint of the brain.

A fully-grown tooth found in the nest suggests that an adult troodontid may have returned to care for the hatchlings.

Fact
or
Fiction
?

Fact

This specimen provides some helpful clues about how troodontid cared for their young.

Troodontids are closely related to birds.

Fact
or
Fiction
?

Fact

The fossil evidence suggests that troodontids and dromaeosaurs are closely related to birds.

Troodontid nest
(troh-uh-DON-tid)
Locality Found: Mongolia
Age: Cretaceous 80 MYA
Size: 12 inches long
Prepared For: Museum exhibit for the year 2000
Characteristics: This rare discovery displays a nest of eggs arranged in a tight circle that was laid by a troodontid dinosaur.

Image credits: courtesy of AMNH; Roy Chapman Andrews: courtesy of AMNH; Amy Davidson: Discovery Channel Online.