Leaellynasaura

Leaellynasaura was a diminutive polar ornithopod dinosaur from the Early Cretaceous of Victoria, Australia, active around 118 to 110 million years ago. Named after the discoverers' daughter, Leaellyn Rich, this small creature grew to about two metres long, but most of that measurement comprised a tail composed of over seventy vertebrae. It lived within the Antarctic Circle of the time, braving months of darkness and sub-zero temperatures. Large eye sockets in its skull suggest keen night vision, useful for foraging through polar winters. It ran on long, slender hind legs and snipped low vegetation using a small beak and ridged cheek teeth, demonstrating the remarkable climatic adaptability of small Cretaceous dinosaurs.

It possessed an extraordinarily long tail, accounting for roughly three-quarters of its total body length.

Where and when

Leaellynasaura lived in the Early Cretaceous, from 118 to 110 million years ago (Aptian-Albian age). Its remains come from Australia, in the Eumeralla Formation.

The numbers

Length 1.9 m (estimates run from 1.5 to 2.2 m). Mass about 11 kg. Hip height about 0.6 m. That is 1.1 human-lengths, or 0.17 of a double-decker bus. These are estimates from partial skeleton; fields marked estimated by the site are length, mass, hip height.

Compare Leaellynasaura with a bus Place on the timeline