Protected in a small piece of amber dating back 99 million years, an ancient skull is changing the timeline researchers have for when reptiles transitioned into the descendants of current-day birds. Found in Myanmar, the oculudentavis khaungraae had at least 23 sharp teeth on its upper jaw, which suggests that the creature ate insects, according to an article published in Nature this week. Its eye was canonical with small pupils and resembles those of a modern lizard, while the edge of the socket indicates that it was well-equipped to see in bright light. About the size of a hummingbird’s, the skull totals .6 inches, although this avian species is thought to be 70 million years older. After archaeopteryx, it’s the most ancient bird ever discovered. To prevent damage to the bone, researchers used X-rays to construct a 3D model that’s shown below.

Update: This article has been corrected to acknowledge an update from Nature that says the skull is no longer believed to be a dinosaur.