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Eoraptor

One of the very first dinosaurs.

Said: EE-oh-RAP-tor

Era: Triassic · 231 million years ago

Diet: Omnivore

Habitat: River valleys of what is now Argentina

Size: about the size of a small dog.

What it was like

Eoraptor was one of the first dinosaurs ever. It was small, light, and ran on two legs. It probably ate both plants and small animals.

What we know now

Position in the dinosaur family tree is debated; once classified as a basal theropod, it is now widely placed as an early sauropodomorph. Heterodont dentition with both leaf-shaped and recurved teeth indicates omnivory. Discovered in 1991 in the Ischigualasto Formation, one of the most productive Triassic sites.

Notes

1. Existed before the major dinosaur lineages had fully diverged.
2. Lived alongside non-dinosaur reptiles still dominant in its ecosystem.
3. Hand had five fingers, with the fourth and fifth already reduced.