Did you know that dinosaurs reproduced by laying eggs and that their closest living relatives are birds? That’s right, the eggs we can confidently date today are from around 85 million years ago and come from the later part of dinosaur history. But what did these eggs look like when dinosaurs roamed the Earth and how can they be recognised in fossil form? Here’s what has been discovered.

What Did Dinosaur Eggs Look Like?

With their sharp teeth, formidable claws and dominant presence, it’s hard to believe that most dinosaurs originated from a calcified egg that would have been off-white, beige or pale brown in colour - a bit like a bird egg but with a thicker shell. Chemical evidence from fossils also shows that some dinosaur eggs were speckled or of a green-blue hue, similar to an emu egg.

Each dinosaur group also laid an egg with a different shell pattern and fossilised shells are still being identified by their unique textures. While Sauropods laid eggs with a pebbly, bumpy texture, Hadrosaurs laid eggs that were smoother, but still grainy. Theropods laid eggs that had long, ridged eggs with a faint linear pattern. 

How Were They Arranged in Nests?

The way eggs were arranged in nests also helped to identify which dinosaur laid them. Theropods often laid elongated eggs in pairs and adults may have sat on them to provide warmth and protection - much like modern day birds. 

Long-necked Sauropods, on the other hand, would have laid round eggs which they buried in sand or soil. They relied on the heat from the environment to help the eggs hatch. Hadrosaurs built mounded nests and their eggs would have been clustered together in a tight group, just like how many modern birds lay several eggs in one nest.

How to Recognise a Real Fossil Dinosaur Egg

Dinosaur eggs are very rare and difficult to spot, but should you be lucky enough to come across a fossil that you think could be an egg, here’s what to look for: 

• Consistent thickness of shell - dinosaur eggs have a shell that’s of a continuous thickness. 
• Curved not flat - fragments represent the shape of a real egg.
• Microscopic pores - if you can spot tiny pores in the eggshell, you might have found the real deal.
• Stone-like shell - the egg shell will be extremely hard and feel rock-like, rather than bone or ceramic.
• Tiny bumps on the inner surface - these bumps are called mammillae and are where the layers of the shell formed. A microscope is often needed to see these.

Dinosaur eggs can easily look like an array of other stones, which is why proper identification is important. 

Watch a baby dinosaur hatch this summer

This summer you have the chance to step back in time and watch a baby dinosaur hatch. Dinosaur World Live, one of the best dinosaur attractions in London, is at the Troubadour Wembley Park Theatre from 28 July - 6 September 2026. This award-winning show introduces families to a host of prehistoric favourites - and make sure you keep an eye on the dinosaur egg, because it’s about to hatch! Search ‘dinosaur event near me’ and book your dinosaur show tickets today for roarsome family fun.