Mei

What it was like

Mei was a tiny feathered troodontid, about the size of a duck. Its most famous skeleton was found curled up with its head tucked under its arm, like a sleeping bird.

That pose is the oldest known sign of bird-like sleeping in a dinosaur. The animal may have died in its sleep, buried by volcanic ash.

Its world

It lived in the Early Cretaceous in what is now northeastern China. Its bones come from the Yixian Formation, where it shared the land with Sinosauropteryx, Sinornithosaurus and Psittacosaurus.

How it was found

Xu and Norell named Mei in 2004. Its full name means "soundly sleeping dragon." A second skeleton in the same pose was found later.