Beyond T. rex

T. rex

Some dinosaurs have all the luck.

They get to be movie stars and popular toys, and their bones attract huge crowds at museums.

You know the ones we are talking about... 

But these popular dinosaurs tell only a small part of the story. Paleontologists have identified over 400 different species of extinct dinosaurs.

To see some strange and unusual dinosaurs you've never heard of (unless you're a paleontologist), explore this cladogram.


This cladogram is like a family tree. It's a way of organizing dinosaurs based on the unique characteristics they share, like a three-toed foot or a hole in the hip socket. 

  • Click on an orange dot to explore a "node." It shows how dinosaurs on a branch of this tree are related by the physical characteristics they share.
  • Click on a dinosaur to discover more about it.
dinosaur hip fossil close up


A special feature shared by dinosaurs is a depression forming a hole in the hip.

saurischia hand fossil


A special feature shared by saurischians is a hand with a big thumb with the fingers getting shorter as you get further from the thumb.

Ornithischian jaw fossil close up


A special feature shared by ornithischians is a special extra bone at the end of their upper jaw which supported a beak.

thyreopod skin bones fossil close up


A special feature shared by thyreophorans is skin with bones embedded in it that formed nodules, plates and spikes.

sauropod neck skeleton close up


A special feature shared by sauropods is at least eleven, and sometimes more, bones in their necks.

bird tail skeleton


A special feature shared by birds is a bony tail that is very short and made of fused tail bones.

theropod foot fossil


A special feature shared by theropods is a foot with 3 main toes for support.

Image Credits:

All dinosaur illustrations: Rick Spears